Date   

Re: New 4K monitor?

Robert Wheeler
 

Although photography is a hobby, I got a BenQ 4K monitor that has a wide color gamut and sits next to an secondary Del monitor that is not 4K and has sRGB color gamut. Both are calibrated using a colorimeter. The BenQ was more affordable than similar EIZO models. On the better monitor, I am able to see a little more detail, better contrast, and colors seem a little richer. Using test images, I can indeed see more colors in the wide gamut monitor. I participated in a test of image appearance over Zoom, where several members of our camera club took turns sharing identical images via our various monitors. Even when viewed at the other end on browsers best suited for sRGB, the images as displayed from my good monitor screen seemed to transmit fine detail better than what the others could send using the same images sent via sharing from their various monitors. Differences in detail were detected based on our verbal discussions of what we could see in the images that had detail in roof shingles, grasses, and the like. Hard to know if the better color survived across so many different systems and types of equipment as we were not in the same room looking at side by side results. The differences between my two monitors are real, perhaps not blowing my socks off entirely, but definitely noticeable during photo editing. Plus I like looking at what I see. No regrets about spending for the upgrade, and no regrets about not spending more. To me, the wider color gamut was particularly worthwhile.
Robert Wheeler


Re: New 4K monitor?

Bevi Chagnon
 

Previous EIZO models have been gorgeous. Looking at images on them brings my eyes “great joy.”

But they’ve always been pricey and beyond my budget.

If I was working full time in Photoshop and imaging, this one would probably be worth it.

 

— — —

Bevi Chagnon  | Designer, Accessibility Technician |  Chagnon@...

— — —

PubCom: Technologists for Accessible Design + Publishing

consulting training development design sec. 508 services

Upcoming classes at www.PubCom.com/classes

— — —

Latest blog-newsletterSimple Guide to Writing Alt-Text

 

From: colortheory@groups.io <colortheory@groups.io> On Behalf Of bill bane
Sent: Tuesday, February 1, 2022 8:36 PM
To: colortheory@groups.io
Subject: [colortheory] New 4K monitor?

 

Does anyone have one of these new high end 4K monitors, and/or know enough to know if they are worthwhile, ignoring the price/cost?

 

https://www.geeky-gadgets.com/hdr-monitors-01-02-2022/

 

 

From: colortheory@groups.io <colortheory@groups.io> On Behalf Of Dan Margulis via groups.io
Sent: Tuesday, February 01, 2022 11:36 AM
To: colortheory@groups.io
Subject: [colortheory] List Rules and Objectives

 

Applied Color Theory list

General Description and Rules

(This document is posted monthly)

 

OBJECTIVE

The objective of this list, supported by voluntary contributions from its members, is to exchange information that may benefit those who have taken or are considering taking my Applied Color Theory courses, or who are interested in techniques covered in my books, plus related topics. This roughly comprises color correction and other methods that aim at creating satisfactory images.

 

ANONYMOUS POSTS PROHIBITED

Our tradition is that all messages to this group must be signed with the member's full name. First names only or "handles" are not acceptable, nor is quoting an anonymous third party. We request that you configure groups.io to include your full name automatically as the sender of any message. That will insure that each post will have your name at the top and make it unnecessary for you to sign the post. If you don’t do this, you risk having your posts rejected or having your moderation status changed if you forget to add your signature.

 

To implement this, find whatever your current name is in the upper right of the groups.io site, click/hold and choose your Account settings. Then, on the left side, click Identity. On the resulting screen choose Account Profile: Edit. On the next screen change Display Name to your own full name, followed by Update Account Profile.

 

Alternatively, if you are using other groups.io groups, you can create a signature line that will apply to everything you post.

 

There are certain valid reasons why a list member might wish to avoid signing his name. For example, the late Ralph Adam Fine was an appeals court judge. He had to be exceedingly cautious about anything he posted, therefore he normally went through me. Others have been granted anonymity because what they posted reflected badly on a boss or a client. 

 

In such cases, please forward the message to me and I will post it if appropriate with a note of explanation and I will, if appropriate, post it the name deleted. If a person has been granted anonymity, I always use “he” on second reference, regardless of the poster’s actual gender. Persons who have been granted anonymity will not be permitted to attack other list members by name. 

 

VOLUNTARY DONATIONS

In December 2020 we opened a “Support the ACT Group” donations portal at

Any funds received will first be used to reimburse me for fees I pay to groups.io, and secondarily for other educational purposes. I do not wish to profit from this as I do from sales of my books.

 

Apparently the groups.io structure doesn’t permit members to make more than one contribution to a given request. Therefore, the original portal has been closed, and a new “2021 Support the ACT Group” established.

 

No one should feel any obligation to make such a donation. The list has always been intended to be free, even more so in the current difficult times. 

 

GROUPS.IO FEATURES

*A member has the ability to “mute” a thread or hashtag so that additions to it will no longer be received. Also, a member who uses Digest mode or does not normally receive e-mails can override the setting and receive a certain thread or hashtag.

*Attachments of images etc. within posts are now allowed.

*Although the archive of messages from yahoogroups has been transferred, the numbering system is no longer the same. Therefore, searching for a message based on a number found in another yahoogroups message won’t work. Search for an appropriate text stream, if there is one, instead.

*A flexible suite of moderation tools enables us to allow many messages to get to the list immediately, without moderator intervention.

*Hashtags are supported although we haven’t done anything to implement them.

*We are an open group. The general public can read our messages, but cannot access our files or photos. 

*Due to it becoming overcrowded, I have reorganized the Files section. All content from 2015 and previous is now in a subfolder. Furthermore, the many Actions that were uploaded in that timeframe have been put in their own sub-subfolder.

 

PLEASE SNIP YOUR QUOTES

Many e-mail programs by default append a complete copy of the message being replied to. Unless that message is a short one, the practice is inappropriate for our group. It becomes a particular problem when the appended message itself appends another. Please be sure that the length of any message being appended is appropriate compared to your own original content.

 

Particularly, if you’re replying to a post that includes an image or other attachment, make sure it doesn’t get repeated in yours. We get charged by the space we use, and one image may take up the space of a thousand text messages.

 

CROSS-POSTINGS TO OTHER GROUPS

It is a breach of etiquette for list members to post the same question to multiple on-line groups simultaneously. People who answer questions on these lists are often experts in the field who are donating generous amounts of their time to assisting those who need guidance. Nobody wants to waste time responding to a question that's already been satisfactorily answered elsewhere.

 

Instead, please post the question here or to whatever other group you think is most likely to be helpful. If you haven't gotten an answer you can live with in, say, 48 hours, by all means try a different list. In such a case, it's only courteous to say something like "I have tried the XXX list, and got no reply" or "I asked this on the YYY list, and was told ZZZ, I'm not sure I accept this, would anyone here care to comment?" 

 

POSTING OF IMAGES and FILES

If you need to refer us to an image, and do not wish to link to some other site, please put it (JPEG only, can be either RGB or CMYK) into the Photos section of the group, setting up a folder if need be.

 

If you need to post a PDF, an action, or any other type of file that is not an image, use the Files section. Groups.io will not permit you to post a JPEG or anything else that it identifies as an image there. In the event that you have to post some form of image in the Files section, you’ll need to zip it first.

 

If you only have one or two images to post, and they don’t belong in a specific folder, please put them into the Miscellaneous folder within the Photos section.

 

Some folders set up by the moderators are locked, i.e. you can look at, download, and comment on pictures, but not add or delete any. Other folders are open and anyone can post pictures to them.

 

The direct link to our Photos section is

The direct link to our Files section is

 

AN INTERNATIONAL GROUP

English is not the first language for many subscribers. If you are using acronyms, please be sure that everyone understands what they mean. Also, the preferred format for dates is 5 March; if you write 3/5/21 this means March 5 in the United States, but it means May 3 in most of the rest of the world.

 

ADVERTISING and COMMERCIAL POSTS

Nobody wants this to become an advertising list, but in practice it is difficult to draw a fine line between a comment and a product plug. Members are requested to use restraint and to ask themselves whether what they are posting is something that a significant number of readers would be interested in. That said, brief plugs are permitted. Similarly, new product announcements are permitted, but the preferred form is to announce briefly and indicate to the list members where further information is available.

 

Repeated commercial posts are prohibited. Also, there will be little to no tolerance for commercial posts from persons who are not otherwise participating in the list. This includes "public service announcements" or posts promoting private websites.

 

Unnecessarily lengthy signature blocks that advertise services are discouraged.

 

CONFLICTS OF INTEREST

Members are entitled to know if posters have commercial affiliations that might affect their views as to the products and topics they post about. If you have such an affiliation, you are expected to disclose it. This doesn't mean in every post, but often enough so that the readers will be in no doubt as to what your biases might be. For the purpose of this list, if you're writing about a certain product, and you've accepted more than $300 from that company within the last five years, that's something that should be disclosed. Similarly, if you have received freebies worth more than $300 during that time, it should be disclosed.

 

Furthermore, if you in the last five years have been a developer of or otherwise represented a certain product, and you are writing about a product that might reasonably said to compete with it, you are expected to disclose this.

 

These rules are not intended to stop you from posting on whatever you like, nor are they intended to force you to give any details at all about the payment. If your signature or company identification (e.g. an adobe.com address) makes your affiliation obvious, there's no need for anything more. Otherwise, a "DISCLOSURE: I have received payments/freebies from this company in the recent past" will suffice.

 

DIGEST MODE

Members who do not want a high volume of single messages may sign up for this list in digest mode. groups.io offers three choices:

1) Full-featured: you get a full copy of all messages sent, including links and attachments, once a day or after 12 new messages have been posted, whichever comes first.

2) Plain digest: same as above, no links or attachments.

3) Daily summary: once a day, shows topics being discussed only, no text.

 

You are not permitted to reply directly to a Digest file, because groups.io doesn’t want you to append the whole digest to your reply. Your own e-mail client may seem to allow it, but your attempt will be directed to a dead mailbox at groups.io. Instead, within the Digest, click Reply below the specific message that you wish to reply to.

 

MODERATION AND INAPPROPRIATE POSTS

This list is moderated, currently by five persons. Traditionally, all posts had to be approved by one of us (Gerald Bakker, Darren Bernaerdt, Sterling Ledet, Dan Margulis, Stephen Marsh), before they were distributed to the group.  With groups.io we implemented a more liberal policy: the first post from any member requires moderator approval (otherwise we might be subjected to spam) but once one message has been approved the user may post directly to the list without our intervention, unless we later decide otherwise.

 

Certain users will remain or become subject to moderation of each post due to having crossed the line on one of the items listed below. Additionally, certain threads will be locked or become subject to moderation if they threaten to get out of control.

 

If you are subject to moderation we will reject the following types of message without prior warning. If you are not currently subject to moderation, posting one of these is a good way to change that status. NOTE: If we reject a post, we send a message to the sender indicating why. If your post hasn't appeared, and you haven't gotten a rejection message (check your spam folder!), probably the message got lost in cyberspace.

 

1) Spam; press releases, product announcements or "classified advertising" from people who haven't participated in the list in at least six months or who are recent signups; form letters; posts from people who don't otherwise participate in the list referring us to private websites; and posts from anyone referring us to links without a reasonably full explanation of what is to be found there.

 

2) Messages in which a full name does not appear.

 

3) Messages that do not have an informative title, e.g. "No Subject" or "Digest #1234"

 

4) Messages responding to messages that are extremely dated or that the rest of the list has not seen at all. Typically, this occurs when Party B replies to Party A offline, and Party A responds to the list.

 

5) Messages that would subject the group to an unreasonable amount of quoted material, such as reposting lengthy, unedited material from other sources, the attachment of a complete message which itself attached additional messages, or simply appending an entire lengthy message rather than snipping the specific material that is of interest.

 

6) Technical questions that the moderator is aware are simultaneously crossposted to other group(s). The moderator will generally not approve other types of simultaneous crossposts but may use discretion in exceptional cases.

 

7) Messages that contain a copyright notice or may present legal problems if posted to the group. 

 

8) Messages that may be hoaxes.

 

9) Messages containing attempts at ethnic or sexual humor, whether or not there is other relevant content.

 

10) Other attempts at humor that the moderator doesn't think are funny and that contain no content relevant to an existing thread.

 

11) Messages that are derisive or dismissive of another member’s skills in photography or color correction. Constructive criticism is welcome but must be framed in a respectful fashion, even if the person being criticized is a beginner.

 

12) "Repeats" of recent posts hoping to get responses that the first ones did not.

 

13) Messages from persons who have been list members for less than six months or who have not posted to the list in the past six months, and which in the judgment of the moderator show a lack of understanding of what the list is about or which duplicate something that has been covered recently. Examples: questions like "how do I calibrate my monitor?"; messages of introduction to the list; questions on topics in which the list does not specialize, and questions on a topic about which a thread has just ended.

 

14) Messages that do not respond to an existing thread and have nothing to do with color or the purposes of this group, e.g. corrections of people's grammar, needless quibbling over terminology or political correctness, statements in support of some political cause, attempts to unsubscribe, virus warnings, or change of address notifications.

 

15) Today's web etiquette countenances certain acronyms (e.g. POS, FUBAR, SOL, BFD) where an off-color word is implied. As long as these words are not spelled out there is no objection. In the interest of decorum, however, we ask members to refrain from undisguised use of locutions found on the commonly available "Seven Filthy Words" list.

 

MODERATION AND CENSORSHIP

We do not wish to censor posts based on their content or to cause people to pull their punches in what they write. We are willing to have reasonably brief threads on almost any color-related topic. Intervention by a moderator to restrict discussion is rare. It will become even rarer in groups.io, since now members have the option of muting a thread that doesn’t interest them. However, it may take place under the following circumstances.

 

1. If in the judgment of the moderators, a thread is going on too long, we will post publicly to the list and to all participants a request to bring it to a close. Our criteria in doing this may include: limited interest of the thread to the vast majority of the group; repetition of the same points over and over; participation only by a few members; or that there was a closely similar recent thread. Unless the list is being deluged, the moderators try to consult with one another before locking a thread. Ordinarily we give the list 24 hours notice that a thread will be ending so that those interested may post their final thoughts on the subject. In the interim, all posts to the thread will require moderator approval. Afterward, the thread will be locked so that no further posts can be accepted. 

 

2. Occasionally a thread has become so acid that a moderator posts a warning about civility, or about bringing in irrelevancies such as discussion of political events. In such cases the thread continues, but all additions to the thread will require moderator approval, and the list is on notice that offending posts are subject to rejection at the discretion of the moderators.

 

3. We reserve the right to limit the sheer volume of posting allowed by any list member or by any interest group that is posting substantially the same type of material.

 

ARCHIVING

This group has existed since 2/99, but in late 12/00 it shifted servers to egroups, later yahoogroups. In 11/19, it moved to groups,io. All yahoogroups messages, files, and photos are accessible at colortheory.groups.io. Note, however, that the yahoogroups message numbering scheme did not carry over to groups.io. Therefore, any archived message that refers to a different one by number will not link to the correct message. Search by text instead.

 

From time to time, we have post edited full threads, at

There are around 300 such threads available. The most recent update was August, 2013. 

 

THE MODERNCOLORWORKFLOW SITE

My book Modern Photoshop Color Workflow was released in March, 2013. In conjunction with it, we opened http://www.moderncolorworkflow.com, which has a variety of materials that might supplement the discussions of this list.

 

RE-USE OF POSTED MATERIAL

In today's information age, the assumption must be that comments posted to groups like this one are for public consumption, and may be freely quoted by others without further permission. Images referred to in group messages, whether posted to this group's photo section or posted on the web sites of others, are a different story. Such images are assumed to be copyrighted material, and no reuse is permissible without the consent of the owner.

 

QUESTIONS AS TO APPROPRIATENESS

If you have doubts as to the propriety of posting something, please feel free to contact me or another moderator directly.

 

UNSUBSCRIBING and POSTING DIFFICULTIES

Every list message contains an Unsubscribe link at the bottom. If you have any difficulty in either unsubscribing or in posting to the group, consider the possibility that you are no longer posting or receiving under the exact address with which you subscribed. 

 

If you attempt to post and receive a message stating that, although you are a member, you are not permitted to post, it means that a moderator has manually disallowed your posting privileges. We do this to members who have sent spam (often the result of a virus) or who have set their mailbox to auto-reply to the group explaining that they are out of the office. If you get this message and wish your rights restored, contact a moderator offline.

 

To change your email address, log into Groups.io. Then look for the dropdown in the top right corner of the page, which will be either your name or email address. Click that and then click Account.

On the edit profile page, you can change your email address. Once you do so, you will receive a new confirmation email. Once you reply to that, you will be all set.

If the email address you wish to change to is already registered with Groups.io, a page will come up explaining the account merge process and verifying that you would like to merge your accounts.

 

LEDET GRAPHICS TRAINING

This list is sponsored by Ledet Graphics Training, which offers a variety of Internet and graphic arts courses, with company-owned facilities in the Atlanta, Chicago, and Washington, DC areas. For further information, visit www.ledet.com or call 877-819-2665 (+1 770-414-5007 from outside U.S.)

 

 

Dan Margulis

Last revised 1 January 2022

Suggestions for revising this document are welcome.

 


New 4K monitor?

bill bane
 

Does anyone have one of these new high end 4K monitors, and/or know enough to know if they are worthwhile, ignoring the price/cost?

 

https://www.geeky-gadgets.com/hdr-monitors-01-02-2022/

 

 

From: colortheory@groups.io <colortheory@groups.io> On Behalf Of Dan Margulis via groups.io
Sent: Tuesday, February 01, 2022 11:36 AM
To: colortheory@groups.io
Subject: [colortheory] List Rules and Objectives

 

Applied Color Theory list

General Description and Rules

(This document is posted monthly)

 

OBJECTIVE

The objective of this list, supported by voluntary contributions from its members, is to exchange information that may benefit those who have taken or are considering taking my Applied Color Theory courses, or who are interested in techniques covered in my books, plus related topics. This roughly comprises color correction and other methods that aim at creating satisfactory images.

 

ANONYMOUS POSTS PROHIBITED

Our tradition is that all messages to this group must be signed with the member's full name. First names only or "handles" are not acceptable, nor is quoting an anonymous third party. We request that you configure groups.io to include your full name automatically as the sender of any message. That will insure that each post will have your name at the top and make it unnecessary for you to sign the post. If you don’t do this, you risk having your posts rejected or having your moderation status changed if you forget to add your signature.

 

To implement this, find whatever your current name is in the upper right of the groups.io site, click/hold and choose your Account settings. Then, on the left side, click Identity. On the resulting screen choose Account Profile: Edit. On the next screen change Display Name to your own full name, followed by Update Account Profile.

 

Alternatively, if you are using other groups.io groups, you can create a signature line that will apply to everything you post.

 

There are certain valid reasons why a list member might wish to avoid signing his name. For example, the late Ralph Adam Fine was an appeals court judge. He had to be exceedingly cautious about anything he posted, therefore he normally went through me. Others have been granted anonymity because what they posted reflected badly on a boss or a client. 

 

In such cases, please forward the message to me and I will post it if appropriate with a note of explanation and I will, if appropriate, post it the name deleted. If a person has been granted anonymity, I always use “he” on second reference, regardless of the poster’s actual gender. Persons who have been granted anonymity will not be permitted to attack other list members by name. 

 

VOLUNTARY DONATIONS

In December 2020 we opened a “Support the ACT Group” donations portal at

Any funds received will first be used to reimburse me for fees I pay to groups.io, and secondarily for other educational purposes. I do not wish to profit from this as I do from sales of my books.

 

Apparently the groups.io structure doesn’t permit members to make more than one contribution to a given request. Therefore, the original portal has been closed, and a new “2021 Support the ACT Group” established.

 

No one should feel any obligation to make such a donation. The list has always been intended to be free, even more so in the current difficult times. 

 

GROUPS.IO FEATURES

*A member has the ability to “mute” a thread or hashtag so that additions to it will no longer be received. Also, a member who uses Digest mode or does not normally receive e-mails can override the setting and receive a certain thread or hashtag.

*Attachments of images etc. within posts are now allowed.

*Although the archive of messages from yahoogroups has been transferred, the numbering system is no longer the same. Therefore, searching for a message based on a number found in another yahoogroups message won’t work. Search for an appropriate text stream, if there is one, instead.

*A flexible suite of moderation tools enables us to allow many messages to get to the list immediately, without moderator intervention.

*Hashtags are supported although we haven’t done anything to implement them.

*We are an open group. The general public can read our messages, but cannot access our files or photos. 

*Due to it becoming overcrowded, I have reorganized the Files section. All content from 2015 and previous is now in a subfolder. Furthermore, the many Actions that were uploaded in that timeframe have been put in their own sub-subfolder.

 

PLEASE SNIP YOUR QUOTES

Many e-mail programs by default append a complete copy of the message being replied to. Unless that message is a short one, the practice is inappropriate for our group. It becomes a particular problem when the appended message itself appends another. Please be sure that the length of any message being appended is appropriate compared to your own original content.

 

Particularly, if you’re replying to a post that includes an image or other attachment, make sure it doesn’t get repeated in yours. We get charged by the space we use, and one image may take up the space of a thousand text messages.

 

CROSS-POSTINGS TO OTHER GROUPS

It is a breach of etiquette for list members to post the same question to multiple on-line groups simultaneously. People who answer questions on these lists are often experts in the field who are donating generous amounts of their time to assisting those who need guidance. Nobody wants to waste time responding to a question that's already been satisfactorily answered elsewhere.

 

Instead, please post the question here or to whatever other group you think is most likely to be helpful. If you haven't gotten an answer you can live with in, say, 48 hours, by all means try a different list. In such a case, it's only courteous to say something like "I have tried the XXX list, and got no reply" or "I asked this on the YYY list, and was told ZZZ, I'm not sure I accept this, would anyone here care to comment?" 

 

POSTING OF IMAGES and FILES

If you need to refer us to an image, and do not wish to link to some other site, please put it (JPEG only, can be either RGB or CMYK) into the Photos section of the group, setting up a folder if need be.

 

If you need to post a PDF, an action, or any other type of file that is not an image, use the Files section. Groups.io will not permit you to post a JPEG or anything else that it identifies as an image there. In the event that you have to post some form of image in the Files section, you’ll need to zip it first.

 

If you only have one or two images to post, and they don’t belong in a specific folder, please put them into the Miscellaneous folder within the Photos section.

 

Some folders set up by the moderators are locked, i.e. you can look at, download, and comment on pictures, but not add or delete any. Other folders are open and anyone can post pictures to them.

 

The direct link to our Photos section is

The direct link to our Files section is

 

AN INTERNATIONAL GROUP

English is not the first language for many subscribers. If you are using acronyms, please be sure that everyone understands what they mean. Also, the preferred format for dates is 5 March; if you write 3/5/21 this means March 5 in the United States, but it means May 3 in most of the rest of the world.

 

ADVERTISING and COMMERCIAL POSTS

Nobody wants this to become an advertising list, but in practice it is difficult to draw a fine line between a comment and a product plug. Members are requested to use restraint and to ask themselves whether what they are posting is something that a significant number of readers would be interested in. That said, brief plugs are permitted. Similarly, new product announcements are permitted, but the preferred form is to announce briefly and indicate to the list members where further information is available.

 

Repeated commercial posts are prohibited. Also, there will be little to no tolerance for commercial posts from persons who are not otherwise participating in the list. This includes "public service announcements" or posts promoting private websites.

 

Unnecessarily lengthy signature blocks that advertise services are discouraged.

 

CONFLICTS OF INTEREST

Members are entitled to know if posters have commercial affiliations that might affect their views as to the products and topics they post about. If you have such an affiliation, you are expected to disclose it. This doesn't mean in every post, but often enough so that the readers will be in no doubt as to what your biases might be. For the purpose of this list, if you're writing about a certain product, and you've accepted more than $300 from that company within the last five years, that's something that should be disclosed. Similarly, if you have received freebies worth more than $300 during that time, it should be disclosed.

 

Furthermore, if you in the last five years have been a developer of or otherwise represented a certain product, and you are writing about a product that might reasonably said to compete with it, you are expected to disclose this.

 

These rules are not intended to stop you from posting on whatever you like, nor are they intended to force you to give any details at all about the payment. If your signature or company identification (e.g. an adobe.com address) makes your affiliation obvious, there's no need for anything more. Otherwise, a "DISCLOSURE: I have received payments/freebies from this company in the recent past" will suffice.

 

DIGEST MODE

Members who do not want a high volume of single messages may sign up for this list in digest mode. groups.io offers three choices:

1) Full-featured: you get a full copy of all messages sent, including links and attachments, once a day or after 12 new messages have been posted, whichever comes first.

2) Plain digest: same as above, no links or attachments.

3) Daily summary: once a day, shows topics being discussed only, no text.

 

You are not permitted to reply directly to a Digest file, because groups.io doesn’t want you to append the whole digest to your reply. Your own e-mail client may seem to allow it, but your attempt will be directed to a dead mailbox at groups.io. Instead, within the Digest, click Reply below the specific message that you wish to reply to.

 

MODERATION AND INAPPROPRIATE POSTS

This list is moderated, currently by five persons. Traditionally, all posts had to be approved by one of us (Gerald Bakker, Darren Bernaerdt, Sterling Ledet, Dan Margulis, Stephen Marsh), before they were distributed to the group.  With groups.io we implemented a more liberal policy: the first post from any member requires moderator approval (otherwise we might be subjected to spam) but once one message has been approved the user may post directly to the list without our intervention, unless we later decide otherwise.

 

Certain users will remain or become subject to moderation of each post due to having crossed the line on one of the items listed below. Additionally, certain threads will be locked or become subject to moderation if they threaten to get out of control.

 

If you are subject to moderation we will reject the following types of message without prior warning. If you are not currently subject to moderation, posting one of these is a good way to change that status. NOTE: If we reject a post, we send a message to the sender indicating why. If your post hasn't appeared, and you haven't gotten a rejection message (check your spam folder!), probably the message got lost in cyberspace.

 

1) Spam; press releases, product announcements or "classified advertising" from people who haven't participated in the list in at least six months or who are recent signups; form letters; posts from people who don't otherwise participate in the list referring us to private websites; and posts from anyone referring us to links without a reasonably full explanation of what is to be found there.

 

2) Messages in which a full name does not appear.

 

3) Messages that do not have an informative title, e.g. "No Subject" or "Digest #1234"

 

4) Messages responding to messages that are extremely dated or that the rest of the list has not seen at all. Typically, this occurs when Party B replies to Party A offline, and Party A responds to the list.

 

5) Messages that would subject the group to an unreasonable amount of quoted material, such as reposting lengthy, unedited material from other sources, the attachment of a complete message which itself attached additional messages, or simply appending an entire lengthy message rather than snipping the specific material that is of interest.

 

6) Technical questions that the moderator is aware are simultaneously crossposted to other group(s). The moderator will generally not approve other types of simultaneous crossposts but may use discretion in exceptional cases.

 

7) Messages that contain a copyright notice or may present legal problems if posted to the group. 

 

8) Messages that may be hoaxes.

 

9) Messages containing attempts at ethnic or sexual humor, whether or not there is other relevant content.

 

10) Other attempts at humor that the moderator doesn't think are funny and that contain no content relevant to an existing thread.

 

11) Messages that are derisive or dismissive of another member’s skills in photography or color correction. Constructive criticism is welcome but must be framed in a respectful fashion, even if the person being criticized is a beginner.

 

12) "Repeats" of recent posts hoping to get responses that the first ones did not.

 

13) Messages from persons who have been list members for less than six months or who have not posted to the list in the past six months, and which in the judgment of the moderator show a lack of understanding of what the list is about or which duplicate something that has been covered recently. Examples: questions like "how do I calibrate my monitor?"; messages of introduction to the list; questions on topics in which the list does not specialize, and questions on a topic about which a thread has just ended.

 

14) Messages that do not respond to an existing thread and have nothing to do with color or the purposes of this group, e.g. corrections of people's grammar, needless quibbling over terminology or political correctness, statements in support of some political cause, attempts to unsubscribe, virus warnings, or change of address notifications.

 

15) Today's web etiquette countenances certain acronyms (e.g. POS, FUBAR, SOL, BFD) where an off-color word is implied. As long as these words are not spelled out there is no objection. In the interest of decorum, however, we ask members to refrain from undisguised use of locutions found on the commonly available "Seven Filthy Words" list.

 

MODERATION AND CENSORSHIP

We do not wish to censor posts based on their content or to cause people to pull their punches in what they write. We are willing to have reasonably brief threads on almost any color-related topic. Intervention by a moderator to restrict discussion is rare. It will become even rarer in groups.io, since now members have the option of muting a thread that doesn’t interest them. However, it may take place under the following circumstances.

 

1. If in the judgment of the moderators, a thread is going on too long, we will post publicly to the list and to all participants a request to bring it to a close. Our criteria in doing this may include: limited interest of the thread to the vast majority of the group; repetition of the same points over and over; participation only by a few members; or that there was a closely similar recent thread. Unless the list is being deluged, the moderators try to consult with one another before locking a thread. Ordinarily we give the list 24 hours notice that a thread will be ending so that those interested may post their final thoughts on the subject. In the interim, all posts to the thread will require moderator approval. Afterward, the thread will be locked so that no further posts can be accepted. 

 

2. Occasionally a thread has become so acid that a moderator posts a warning about civility, or about bringing in irrelevancies such as discussion of political events. In such cases the thread continues, but all additions to the thread will require moderator approval, and the list is on notice that offending posts are subject to rejection at the discretion of the moderators.

 

3. We reserve the right to limit the sheer volume of posting allowed by any list member or by any interest group that is posting substantially the same type of material.

 

ARCHIVING

This group has existed since 2/99, but in late 12/00 it shifted servers to egroups, later yahoogroups. In 11/19, it moved to groups,io. All yahoogroups messages, files, and photos are accessible at colortheory.groups.io. Note, however, that the yahoogroups message numbering scheme did not carry over to groups.io. Therefore, any archived message that refers to a different one by number will not link to the correct message. Search by text instead.

 

From time to time, we have post edited full threads, at

There are around 300 such threads available. The most recent update was August, 2013. 

 

THE MODERNCOLORWORKFLOW SITE

My book Modern Photoshop Color Workflow was released in March, 2013. In conjunction with it, we opened http://www.moderncolorworkflow.com, which has a variety of materials that might supplement the discussions of this list.

 

RE-USE OF POSTED MATERIAL

In today's information age, the assumption must be that comments posted to groups like this one are for public consumption, and may be freely quoted by others without further permission. Images referred to in group messages, whether posted to this group's photo section or posted on the web sites of others, are a different story. Such images are assumed to be copyrighted material, and no reuse is permissible without the consent of the owner.

 

QUESTIONS AS TO APPROPRIATENESS

If you have doubts as to the propriety of posting something, please feel free to contact me or another moderator directly.

 

UNSUBSCRIBING and POSTING DIFFICULTIES

Every list message contains an Unsubscribe link at the bottom. If you have any difficulty in either unsubscribing or in posting to the group, consider the possibility that you are no longer posting or receiving under the exact address with which you subscribed. 

 

If you attempt to post and receive a message stating that, although you are a member, you are not permitted to post, it means that a moderator has manually disallowed your posting privileges. We do this to members who have sent spam (often the result of a virus) or who have set their mailbox to auto-reply to the group explaining that they are out of the office. If you get this message and wish your rights restored, contact a moderator offline.

 

To change your email address, log into Groups.io. Then look for the dropdown in the top right corner of the page, which will be either your name or email address. Click that and then click Account.

On the edit profile page, you can change your email address. Once you do so, you will receive a new confirmation email. Once you reply to that, you will be all set.

If the email address you wish to change to is already registered with Groups.io, a page will come up explaining the account merge process and verifying that you would like to merge your accounts.

 

LEDET GRAPHICS TRAINING

This list is sponsored by Ledet Graphics Training, which offers a variety of Internet and graphic arts courses, with company-owned facilities in the Atlanta, Chicago, and Washington, DC areas. For further information, visit www.ledet.com or call 877-819-2665 (+1 770-414-5007 from outside U.S.)

 

 

Dan Margulis

Last revised 1 January 2022

Suggestions for revising this document are welcome.

 


List Rules and Objectives

Dan Margulis
 

Applied Color Theory list
General Description and Rules
(This document is posted monthly)

OBJECTIVE
The objective of this list, supported by voluntary contributions from its members, is to exchange information that may benefit those who have taken or are considering taking my Applied Color Theory courses, or who are interested in techniques covered in my books, plus related topics. This roughly comprises color correction and other methods that aim at creating satisfactory images.

ANONYMOUS POSTS PROHIBITED
Our tradition is that all messages to this group must be signed with the member's full name. First names only or "handles" are not acceptable, nor is quoting an anonymous third party. We request that you configure groups.io to include your full name automatically as the sender of any message. That will insure that each post will have your name at the top and make it unnecessary for you to sign the post. If you don’t do this, you risk having your posts rejected or having your moderation status changed if you forget to add your signature.

To implement this, find whatever your current name is in the upper right of the groups.io site, click/hold and choose your Account settings. Then, on the left side, click Identity. On the resulting screen choose Account Profile: Edit. On the next screen change Display Name to your own full name, followed by Update Account Profile.

Alternatively, if you are using other groups.io groups, you can create a signature line that will apply to everything you post.

There are certain valid reasons why a list member might wish to avoid signing his name. For example, the late Ralph Adam Fine was an appeals court judge. He had to be exceedingly cautious about anything he posted, therefore he normally went through me. Others have been granted anonymity because what they posted reflected badly on a boss or a client. 

In such cases, please forward the message to me and I will post it if appropriate with a note of explanation and I will, if appropriate, post it the name deleted. If a person has been granted anonymity, I always use “he” on second reference, regardless of the poster’s actual gender. Persons who have been granted anonymity will not be permitted to attack other list members by name. 

VOLUNTARY DONATIONS
In December 2020 we opened a “Support the ACT Group” donations portal at
Any funds received will first be used to reimburse me for fees I pay to groups.io, and secondarily for other educational purposes. I do not wish to profit from this as I do from sales of my books.

Apparently the groups.io structure doesn’t permit members to make more than one contribution to a given request. Therefore, the original portal has been closed, and a new “2021 Support the ACT Group” established.

No one should feel any obligation to make such a donation. The list has always been intended to be free, even more so in the current difficult times. 

GROUPS.IO FEATURES
*A member has the ability to “mute” a thread or hashtag so that additions to it will no longer be received. Also, a member who uses Digest mode or does not normally receive e-mails can override the setting and receive a certain thread or hashtag.
*Attachments of images etc. within posts are now allowed.
*Although the archive of messages from yahoogroups has been transferred, the numbering system is no longer the same. Therefore, searching for a message based on a number found in another yahoogroups message won’t work. Search for an appropriate text stream, if there is one, instead.
*A flexible suite of moderation tools enables us to allow many messages to get to the list immediately, without moderator intervention.
*Hashtags are supported although we haven’t done anything to implement them.
*We are an open group. The general public can read our messages, but cannot access our files or photos. 
*Due to it becoming overcrowded, I have reorganized the Files section. All content from 2015 and previous is now in a subfolder. Furthermore, the many Actions that were uploaded in that timeframe have been put in their own sub-subfolder.

PLEASE SNIP YOUR QUOTES
Many e-mail programs by default append a complete copy of the message being replied to. Unless that message is a short one, the practice is inappropriate for our group. It becomes a particular problem when the appended message itself appends another. Please be sure that the length of any message being appended is appropriate compared to your own original content.

Particularly, if you’re replying to a post that includes an image or other attachment, make sure it doesn’t get repeated in yours. We get charged by the space we use, and one image may take up the space of a thousand text messages.

CROSS-POSTINGS TO OTHER GROUPS
It is a breach of etiquette for list members to post the same question to multiple on-line groups simultaneously. People who answer questions on these lists are often experts in the field who are donating generous amounts of their time to assisting those who need guidance. Nobody wants to waste time responding to a question that's already been satisfactorily answered elsewhere.

Instead, please post the question here or to whatever other group you think is most likely to be helpful. If you haven't gotten an answer you can live with in, say, 48 hours, by all means try a different list. In such a case, it's only courteous to say something like "I have tried the XXX list, and got no reply" or "I asked this on the YYY list, and was told ZZZ, I'm not sure I accept this, would anyone here care to comment?" 

POSTING OF IMAGES and FILES
If you need to refer us to an image, and do not wish to link to some other site, please put it (JPEG only, can be either RGB or CMYK) into the Photos section of the group, setting up a folder if need be.

If you need to post a PDF, an action, or any other type of file that is not an image, use the Files section. Groups.io will not permit you to post a JPEG or anything else that it identifies as an image there. In the event that you have to post some form of image in the Files section, you’ll need to zip it first.

If you only have one or two images to post, and they don’t belong in a specific folder, please put them into the Miscellaneous folder within the Photos section.

Some folders set up by the moderators are locked, i.e. you can look at, download, and comment on pictures, but not add or delete any. Other folders are open and anyone can post pictures to them.

The direct link to our Photos section is
The direct link to our Files section is

AN INTERNATIONAL GROUP
English is not the first language for many subscribers. If you are using acronyms, please be sure that everyone understands what they mean. Also, the preferred format for dates is 5 March; if you write 3/5/21 this means March 5 in the United States, but it means May 3 in most of the rest of the world.

ADVERTISING and COMMERCIAL POSTS
Nobody wants this to become an advertising list, but in practice it is difficult to draw a fine line between a comment and a product plug. Members are requested to use restraint and to ask themselves whether what they are posting is something that a significant number of readers would be interested in. That said, brief plugs are permitted. Similarly, new product announcements are permitted, but the preferred form is to announce briefly and indicate to the list members where further information is available.

Repeated commercial posts are prohibited. Also, there will be little to no tolerance for commercial posts from persons who are not otherwise participating in the list. This includes "public service announcements" or posts promoting private websites.

Unnecessarily lengthy signature blocks that advertise services are discouraged.

CONFLICTS OF INTEREST
Members are entitled to know if posters have commercial affiliations that might affect their views as to the products and topics they post about. If you have such an affiliation, you are expected to disclose it. This doesn't mean in every post, but often enough so that the readers will be in no doubt as to what your biases might be. For the purpose of this list, if you're writing about a certain product, and you've accepted more than $300 from that company within the last five years, that's something that should be disclosed. Similarly, if you have received freebies worth more than $300 during that time, it should be disclosed.

Furthermore, if you in the last five years have been a developer of or otherwise represented a certain product, and you are writing about a product that might reasonably said to compete with it, you are expected to disclose this.

These rules are not intended to stop you from posting on whatever you like, nor are they intended to force you to give any details at all about the payment. If your signature or company identification (e.g. an adobe.com address) makes your affiliation obvious, there's no need for anything more. Otherwise, a "DISCLOSURE: I have received payments/freebies from this company in the recent past" will suffice.

DIGEST MODE
Members who do not want a high volume of single messages may sign up for this list in digest mode. groups.io offers three choices:
1) Full-featured: you get a full copy of all messages sent, including links and attachments, once a day or after 12 new messages have been posted, whichever comes first.
2) Plain digest: same as above, no links or attachments.
3) Daily summary: once a day, shows topics being discussed only, no text.

You are not permitted to reply directly to a Digest file, because groups.io doesn’t want you to append the whole digest to your reply. Your own e-mail client may seem to allow it, but your attempt will be directed to a dead mailbox at groups.io. Instead, within the Digest, click Reply below the specific message that you wish to reply to.

MODERATION AND INAPPROPRIATE POSTS
This list is moderated, currently by five persons. Traditionally, all posts had to be approved by one of us (Gerald Bakker, Darren Bernaerdt, Sterling Ledet, Dan Margulis, Stephen Marsh), before they were distributed to the group.  With groups.io we implemented a more liberal policy: the first post from any member requires moderator approval (otherwise we might be subjected to spam) but once one message has been approved the user may post directly to the list without our intervention, unless we later decide otherwise.

Certain users will remain or become subject to moderation of each post due to having crossed the line on one of the items listed below. Additionally, certain threads will be locked or become subject to moderation if they threaten to get out of control.

If you are subject to moderation we will reject the following types of message without prior warning. If you are not currently subject to moderation, posting one of these is a good way to change that status. NOTE: If we reject a post, we send a message to the sender indicating why. If your post hasn't appeared, and you haven't gotten a rejection message (check your spam folder!), probably the message got lost in cyberspace.

1) Spam; press releases, product announcements or "classified advertising" from people who haven't participated in the list in at least six months or who are recent signups; form letters; posts from people who don't otherwise participate in the list referring us to private websites; and posts from anyone referring us to links without a reasonably full explanation of what is to be found there.

2) Messages in which a full name does not appear.

3) Messages that do not have an informative title, e.g. "No Subject" or "Digest #1234"

4) Messages responding to messages that are extremely dated or that the rest of the list has not seen at all. Typically, this occurs when Party B replies to Party A offline, and Party A responds to the list.

5) Messages that would subject the group to an unreasonable amount of quoted material, such as reposting lengthy, unedited material from other sources, the attachment of a complete message which itself attached additional messages, or simply appending an entire lengthy message rather than snipping the specific material that is of interest.

6) Technical questions that the moderator is aware are simultaneously crossposted to other group(s). The moderator will generally not approve other types of simultaneous crossposts but may use discretion in exceptional cases.

7) Messages that contain a copyright notice or may present legal problems if posted to the group. 

8) Messages that may be hoaxes.

9) Messages containing attempts at ethnic or sexual humor, whether or not there is other relevant content.

10) Other attempts at humor that the moderator doesn't think are funny and that contain no content relevant to an existing thread.

11) Messages that are derisive or dismissive of another member’s skills in photography or color correction. Constructive criticism is welcome but must be framed in a respectful fashion, even if the person being criticized is a beginner.

12) "Repeats" of recent posts hoping to get responses that the first ones did not.

13) Messages from persons who have been list members for less than six months or who have not posted to the list in the past six months, and which in the judgment of the moderator show a lack of understanding of what the list is about or which duplicate something that has been covered recently. Examples: questions like "how do I calibrate my monitor?"; messages of introduction to the list; questions on topics in which the list does not specialize, and questions on a topic about which a thread has just ended.

14) Messages that do not respond to an existing thread and have nothing to do with color or the purposes of this group, e.g. corrections of people's grammar, needless quibbling over terminology or political correctness, statements in support of some political cause, attempts to unsubscribe, virus warnings, or change of address notifications.

15) Today's web etiquette countenances certain acronyms (e.g. POS, FUBAR, SOL, BFD) where an off-color word is implied. As long as these words are not spelled out there is no objection. In the interest of decorum, however, we ask members to refrain from undisguised use of locutions found on the commonly available "Seven Filthy Words" list.

MODERATION AND CENSORSHIP
We do not wish to censor posts based on their content or to cause people to pull their punches in what they write. We are willing to have reasonably brief threads on almost any color-related topic. Intervention by a moderator to restrict discussion is rare. It will become even rarer in groups.io, since now members have the option of muting a thread that doesn’t interest them. However, it may take place under the following circumstances.

1. If in the judgment of the moderators, a thread is going on too long, we will post publicly to the list and to all participants a request to bring it to a close. Our criteria in doing this may include: limited interest of the thread to the vast majority of the group; repetition of the same points over and over; participation only by a few members; or that there was a closely similar recent thread. Unless the list is being deluged, the moderators try to consult with one another before locking a thread. Ordinarily we give the list 24 hours notice that a thread will be ending so that those interested may post their final thoughts on the subject. In the interim, all posts to the thread will require moderator approval. Afterward, the thread will be locked so that no further posts can be accepted. 

2. Occasionally a thread has become so acid that a moderator posts a warning about civility, or about bringing in irrelevancies such as discussion of political events. In such cases the thread continues, but all additions to the thread will require moderator approval, and the list is on notice that offending posts are subject to rejection at the discretion of the moderators.

3. We reserve the right to limit the sheer volume of posting allowed by any list member or by any interest group that is posting substantially the same type of material.

ARCHIVING
This group has existed since 2/99, but in late 12/00 it shifted servers to egroups, later yahoogroups. In 11/19, it moved to groups,io. All yahoogroups messages, files, and photos are accessible at colortheory.groups.io. Note, however, that the yahoogroups message numbering scheme did not carry over to groups.io. Therefore, any archived message that refers to a different one by number will not link to the correct message. Search by text instead.

From time to time, we have post edited full threads, at
There are around 300 such threads available. The most recent update was August, 2013. 

THE MODERNCOLORWORKFLOW SITE
My book Modern Photoshop Color Workflow was released in March, 2013. In conjunction with it, we opened http://www.moderncolorworkflow.com, which has a variety of materials that might supplement the discussions of this list.

RE-USE OF POSTED MATERIAL
In today's information age, the assumption must be that comments posted to groups like this one are for public consumption, and may be freely quoted by others without further permission. Images referred to in group messages, whether posted to this group's photo section or posted on the web sites of others, are a different story. Such images are assumed to be copyrighted material, and no reuse is permissible without the consent of the owner.

QUESTIONS AS TO APPROPRIATENESS
If you have doubts as to the propriety of posting something, please feel free to contact me or another moderator directly.

UNSUBSCRIBING and POSTING DIFFICULTIES
Every list message contains an Unsubscribe link at the bottom. If you have any difficulty in either unsubscribing or in posting to the group, consider the possibility that you are no longer posting or receiving under the exact address with which you subscribed. 

If you attempt to post and receive a message stating that, although you are a member, you are not permitted to post, it means that a moderator has manually disallowed your posting privileges. We do this to members who have sent spam (often the result of a virus) or who have set their mailbox to auto-reply to the group explaining that they are out of the office. If you get this message and wish your rights restored, contact a moderator offline.

To change your email address, log into Groups.io. Then look for the dropdown in the top right corner of the page, which will be either your name or email address. Click that and then click Account.

On the edit profile page, you can change your email address. Once you do so, you will receive a new confirmation email. Once you reply to that, you will be all set.

If the email address you wish to change to is already registered with Groups.io, a page will come up explaining the account merge process and verifying that you would like to merge your accounts.


LEDET GRAPHICS TRAINING
This list is sponsored by Ledet Graphics Training, which offers a variety of Internet and graphic arts courses, with company-owned facilities in the Atlanta, Chicago, and Washington, DC areas. For further information, visit www.ledet.com or call 877-819-2665 (+1 770-414-5007 from outside U.S.)


Dan Margulis
Last revised 1 January 2022
Suggestions for revising this document are welcome.


Re: Scanning old photos with faded dyes

Michael Colby
 

The Law of Simultaneous Contrast of Color

The Law


Re: Scanning old photos with faded dyes

Michael Colby
 

no reason to leave us just for that. 

You came the for scanning. you could stay for the entertainment and for the law.  The Law of Simultaneous Contrast....


Re: Quantifying Simultaneous Contrast

Beat C
 

On 24 Jan 2022 08:37:53 PST  Dan Margulis wrote :

>>  The idea is an interesting one but it would only show that perceptions differ with the individual.

>> It’s true that AFAWK the visual systems of all human beings respond to simultaneous contrast, but that is a very macro statement and the question of how much they respond to it is very micro. 


Yes, I agree, the measurements will be individual. But I suspect that the distribution will be Gaussian, like most distributions. That way it might be a bit more meaningful than ‘just individual’.

Also, if measurements with X individuals give the same global results, say that the Simultaneous Contrast is stronger in the Luminosity aspect than in the Hue aspect, or that there are differences (or no differences) with different opposite color pairs, we have learned something.



>>  A color-blind person perceives greater difference between adjoining colors than when the two colors are distant from one another just as a normally-sighted, but nobody would suggest that the two perceive the same degree of  shift either in hue or luminosity. 
>> And color-blindness comes in many different degrees, ranging from people with a slight impairment to those who can’t see a difference if the A channel of LAB is inverted.


I suppose that Color Blindness can be measured (to a certain degree), so there could be a correlation function (a sort of normalizing formula) in comparing the results of the Color Blindness tests and the results of test for Simultaneous Contrast. This to try to account for the Color Blindness effect in the tests. 


And even for one individual, it might be interesting to know which of the factors (Luminosity, Hue or Saturation) delivers the biggest contribution to the effect. 
I for one, am glad to know that for me the Luminosity has a bigger effect than the Hue in the SimContrast.


Best, Beat


Re: Scanning old photos with faded dyes

Bruce Bowman <bruce.bowman@...>
 

Folks -- As promised, just following up on this thread that I initiated a week or two ago.

Recall that the idea was to merge the colors from an old, low-res scan into the luminance (but poor color balance) of a newer, high-resolution scan in an attempt to get the best of both.

In practice, I am not getting the improved resolution that I wanted to achieve.

And it's proving very difficult to get the scans in register to begin with...possibly due to the behavior of the two different flatbed scanners that were used. If simply scaling up the original scan provides as good or better than I can get by jumping through all these hoops; well, there's little reason to pursue it.

I am unsubscribing now and will not receive further replies. I am much obliged to all of you who have attempted to assist me in this.

Regards,
Bruce


Re: Quantifying Simultaneous Contrast

Dan Margulis
 


On Jan 22, 2022, at 12:43 PM, Beat C <b.cornaz@...> wrote:

It’s more than a year since I read Dan’s latest book (the translation, annotation and supplementation of Chevreui’s work).
I have always enjoyed reading Dan’s books. This book, though easier to understand, is much tougher to read and that is not Dan’s fault, but the terrible writing style of Chevreul.
I was always pleased when I came across a part that Dan had written in the book. A kind of oasis in the desert. 
Mind you, I think it’s an important book and is well worth reading, but it takes stamina :-)

Anyway, I had this idea shortly after having read the book, but only did one little test. And I do not seem to be able to afford the time to do further experimentation, so maybe it’s time to just present the idea in the rough.

In the book it is mentioned that it is hard or even impossible to quantify or measure the amount of Simultaneous Contrast adaption that occurs in our brain. What about the following way :

The idea is an interesting one but it would only show that perceptions differ with the individual.

It’s true that AFAWK the visual systems of all human beings respond to simultaneous contrast, but that is a very macro statement and the question of how much they respond to it is very micro. A color-blind person perceives greater difference between adjoining colors than when the two colors are distant from one another just as a normally-sighted, but nobody would suggest that the two perceive the same degree of shift either in hue or luminosity. And color-blindness comes in many different degrees, ranging from people with a slight impairment to those who can’t see a difference if the A channel of LAB is inverted.

And we don’t have to limit it to people with a severe deficiency. When I had cataract surgery on both eyes two weeks apart, I spent several hours testing my vision when I had one bad eye and one good one. With one eye closed I would get different results from then the other one was, to the point where if asked to choose between three versions of the same image I would choose a certain one as the best with one eye and as the worst with the other. Yet each eye was affected by simultaneous contrast, just in mildly different ways.


Quantifying Simultaneous Contrast

Beat C
 

It’s more than a year since I read Dan’s latest book (the translation, annotation and supplementation of Chevreui’s work).
I have always enjoyed reading Dan’s books. This book, though easier to understand, is much tougher to read and that is not Dan’s fault, but the terrible writing style of Chevreul.
I was always pleased when I came across a part that Dan had written in the book. A kind of oasis in the desert.
Mind you, I think it’s an important book and is well worth reading, but it takes stamina :-)

Anyway, I had this idea shortly after having read the book, but only did one little test. And I do not seem to be able to afford the time to do further experimentation, so maybe it’s time to just present the idea in the rough.

In the book it is mentioned that it is hard or even impossible to quantify or measure the amount of Simultaneous Contrast adaption that occurs in our brain. What about the following way :

In PhotoShop or another Lab capable application make a setup. Two rectangles with each a smaller rectangle within (same sizes).
Give the bigger rectangles different colors, e.g. complementary colors (or luminosities) and give the smaller rectangles within the bigger ones another, but equal color or luminosity (e.g. mid gray).
Now convert the doc to Lab. The smaller rectangles are the same, but look different, due to the Simultaneous Contrast effect. Now adjust the second small rectangle in such a way that it LOOKS the same to the you as the first one (Curves). So now the smaller rectangles look the same, but are in numbers not the same anymore. (It’s a bit as between ‘Assign Profile’ and ‘Convert to Profile’).
In the info palette compare the two smaller rectangles and the differences give you the amount of Simultaneous Contrast FOR THIS COMBINATION OF 3 COLORS (and/or LUMINOSITIES).

My assumption here is that this reversed way, is equal in a quantitative way, as the normal way, which we cannot measure. I have no proof, but I might be right. Even if I am not right, then still the relative effects can be compared this way.

It might turn out, that the amount of adjusting turns out to be different for different people. Probably is in at least a small amount.
A mean over many tests with many persons can give a good average.

I think it will turn out useful, to separate the Simultaneous Contrast effect on Color and on Luminosity. Maybe after that, the effect of both at the same time and also testing if one (e.g. Color) will affect the outcome of the other (in this case then Luminosity).

Also, do different colors as a comparable pair have different amounts of Simultaneous Contrast?
E.g. Lab (70,30,0) &  (70,-30,0)   versus   (70,0,30) &  (70,0,-30). So the combination Magenta/Green  versus Yellow/Blue.

I guess the tests can get quite elaborate, but I just have to many other things on the stove :-)

Beat


Re: Scanning old photos with faded dyes

Paco
 
Edited

Hi! Bruce, when it all gets too complicated, I've ended up converting the photos to B&W. You might be able to work with some of the colors still present by intensifying them or completely changing them in color and saturation to get more tonal variety and separation when converting to B&W. Of course, if the colors in the photo are all important, then this advise is useless. All the best!

Paco


Re: Scanning old photos with faded dyes

Dan Margulis
 



On Jan 13, 2022, at 8:10 AM, Bruce Bowman <bruce.bowman@...> wrote:

My wife and I held a Halloween party for 38 consecutive years (1982-2019) and we've collected extensive documentation of it. For the first 20 or so, I was still using film. The photos from first three years (roughly 100 of them) are the worst. After that, I must have used a different photo processor -- those prints have held up a lot better, and I haven't had to resort to such measures to restore them. 

If those first hundred all have approximately the same defect (sounds like the magenta colorant didn’t hold up as well as the others) then the smart thing would be to find one of the images that happens to be easy to correct, and then apply the same correction to the others. That will at least get you close.

Look for a picture that has large dark objects that are known specifically to be *black*. Probably at the moment they’re greenish. Then on a curves adjustment layer, use the eyedropper tool to force them to become black. That should get the image a lot closer to where it should be. And that adjustment layer can be dragged onto any number of other similar images.

One of the many problems with this kind of work is that the deterioration isn’t uniform. Some of these hundred won’t really show the same defect as the others. Also, the defect can be worse in a certain range (say the highlights) or in a certain area (say the upper right of the print). In such cases there’s nothing to do but suck it up and correct manually.


Re: Scanning old photos with faded dyes

Doug Schafer
 

Also, you can try the Ps ai/neural tool/filter 'colorize' to auto color images....try converting to B&W and then adjust colors to match your "correct" lo-res sample.


Re: Scanning old photos with faded dyes

Bruce Jamieson
 

Hector knows what’s up!
–B

On Jan 12, 2022, at 1:45 PM, Hector Davila <amerphoto@...> wrote:

You would have to read ALL of
Dan Margulis books to win the contest.


Re: Scanning old photos with faded dyes

Bruce Bowman <bruce.bowman@...>
 

Folks -- Just wanted to thank those who have responded to my inquiry. 

My wife and I held a Halloween party for 38 consecutive years (1982-2019) and we've collected extensive documentation of it. For the first 20 or so, I was still using film. The photos from first three years (roughly 100 of them) are the worst. After that, I must have used a different photo processor -- those prints have held up a lot better, and I haven't had to resort to such measures to restore them.

And yes, I am fortunate to have those previous images. With a lot of people in makeup (or other forms of gaudy disarray), I can't always count on "flesh tone" to gauge what the original may have looked like! And as you might imagine, I have a number of other photos in need of this kind of work but don't have any older scans to help me.  :-(

Anyway, I now have everything I need and also some good advice. I plan to tackle this sometime over the next month or so (i.e.: after I get done re-scanning the remaining 17 years). When that's done I intend to report back on my findings.

Thanks again,
Bruce


Re: Scanning old photos with faded dyes

Hector Davila
 

You are lucky to have
low-resolution scans of these same photos
with good color balance.

But imagine if you didn't.

Then you would have to
color correct without
knowing what the other
same photo with
good color balance
looks like.

It would make a good contest photo.

See who comes closer
to the original photo
good color balance
without looking at it.


You would have to read ALL of
Dan Margulis books to win the contest.




Hector Davila






On 1/12/2022 1:35 AM, Bruce Bowman wrote:
Hi. New member, new topic, but perhaps familiar to many of you.

I have some old photos whose dyes have faded terribly...especially the blue. People's blue jeans look green. Using auto-levelling helps some, but you can't boost blue that just isn't there.

 

I also have some low-resolution scans of these same photos that were done many years ago. The image scale is bad, but the color balance is good.

 

What I'd like to do is somehow merge the hi-resolution scans I'm doing now with the colors from the older images. Any thoughts on how this could be done?

 

Thanks,

Bruce

_._,_._,_


 


Re: Scanning old photos with faded dyes

Doug Schafer
 

Others have good ideas and maybe combine those with:

Try up-sampling (like gigapixel ai or other program to increase resolution; including Ps) on the lo-res images to match the other image size/resolution and blend the color of up-scaled lo res with the luminosity of the larger/hi-res image.


Re: Scanning old photos with faded dyes

Bruce Jamieson
 

Photoshop. I think you could also do this with Affinity Photo. As long as whatever program has a layer blending mode called “Color” you should be good. Gimp, or maybe try out https://www.photopea.com.

Working in the Lab color space would let you do something very similar, which Photoshop and Affinity Photo are capable of, but you might have to do some further reading.

Good luck!
Bruce

On Jan 12, 2022, at 11:06 AM, Bruce Bowman <bruce.bowman@...> wrote:

On Wed, Jan 12, 2022 at 09:01 AM, Bruce Jamieson wrote:
A secret technique from one Bruce to another. Can the two images be reasonably aligned? Put the better-color-but-low-res image on top of the high-res-but-lousy scan, and set the blending mode to “Color.” Magic.
Thanks Bruce. I will need to know what software we are talking about.

Thanks,
Bruce (the other one)


Re: Scanning old photos with faded dyes

Bruce Bowman <bruce.bowman@...>
 

On Wed, Jan 12, 2022 at 09:01 AM, Bruce Jamieson wrote:
A secret technique from one Bruce to another. Can the two images be reasonably aligned? Put the better-color-but-low-res image on top of the high-res-but-lousy scan, and set the blending mode to “Color.” Magic.
Thanks Bruce. I will need to know what software we are talking about.

Thanks,
Bruce (the other one)


Re: Scanning old photos with faded dyes

Bruce Bowman <bruce.bowman@...>
 

On Wed, Jan 12, 2022 at 08:14 AM, Stephen Marsh wrote:
Of course, the L channel of Lab or the luminosity component of RGB will have an effect on the colour, so it is not always "that easy".
Agreed. My experience so far with freeware software suggests that it's not going to be a trivial exercise. I can enlarge the old scan to match the new one's image scale, but getting the two images completely in register will no doubt be part of the challenge.

Bruce

121 - 140 of 33424