A column on white point


Dan Margulis
 

Here in New Jersey, for obvious reasons I’ve had a lot of time on my hands and have been using it to clean up some older stuff, including scanning some old magazine columns.

As it happens, twenty years ago I wrote something that because of its very simplicity is potentially more valuable today than it was back then. It’s called “The Great Imaging Equalizer”, and it talks about how the command that we today know as Auto Tone sometimes lets absolute beginners make better corrections than people who consider themselves experts. That leads to a discussion of why it succeeds when it does, why it fails when it doesn’t choose the correct endpoints, and how even an inexperienced person can do better by selecting his own with the eyedropper.

The advent of PPW and other high-powered fancy workflows can make us forget these basics. Anyone who doesn't set good white and black points, whether you, me, Caravaggio, or Monet, will not get satisfactory results. Even after twenty years, IMHO, it's worth a read, regardless of how basic it seems, so I've posted a PDF.

Will people be interested in checking it out? Well, nobody knows what the current situation does to people's psychology. Most of the time now I don't feel inclined to do anything involving color or Photoshop and I suspect others feel the same way. OTOH with so many of us prisoners in our own homes there's a lot of time to study and experiment if so inclined. We've talked about doing some case studies here, where we post a problematic image or two, have members try to correct it, and post and comment on the results. I'm game for it if others are.

Meanwhile, here's the link for the white point column.

And here's the link for all the columns posted so far.

Stay healthy, everybody.

Dan


David Riecks
 

Dan:
I know of some others who would be interested. Do I have your permission to "reprint" your post above (not just the links) along with suitable attribution? 
David


Dan Margulis
 


On May 2, 2020, at 11:59 AM, David Riecks <david@...> wrote:

Dan:
I know of some others who would be interested. Do I have your permission to "reprint" your post above (not just the links) along with suitable attribution? 

Certainly. All posts to this list should be considered in the public domain. Images, no, but text, yes.

Dan Margulis


James Gray
 

D. Margulis:  Well, nobody knows what the current situation does to people's psychology. Most of the time now I don't feel inclined to do anything involving color or Photoshop and I suspect others feel the same way. OTOH with so many of us prisoners in our own homes there's a lot of time to study and experiment if so inclined. We've talked about doing some case studies here, where we post a problematic image or two, have members try to correct it, and post and comment on the results. I'm game for it if others are.

James Gray:  Fortunately for me being confined to my home has not been a lot different from the way my life was before as an old retired guy.  The biggest change is that I do not travel as much and consequently have not taken travel photographs.  I would be very interested in observing or participating in some case studies of problematic images.  In particular I would like to see steps that integrate with the PPW for creating final images that are competitive with or use tools like luminosity masks or ALCE to create the kind of snap, pop, or impact that a lot of images have now in comparison to a dozen years ago.

James Gray

On Sat, May 2, 2020 at 9:49 AM Dan Margulis via groups.io <dmargulis=aol.com@groups.io> wrote:
Here in New Jersey, for obvious reasons I’ve had a lot of time on my hands and have been using it to clean up some older stuff, including scanning some old magazine columns.

As it happens, twenty years ago I wrote something that because of its very simplicity is potentially more valuable today than it was back then. It’s called “The Great Imaging Equalizer”, and it talks about how the command that we today know as Auto Tone sometimes lets absolute beginners make better corrections than people who consider themselves experts. That leads to a discussion of why it succeeds when it does, why it fails when it doesn’t choose the correct endpoints, and how even an inexperienced person can do better by selecting his own with the eyedropper.

The advent of PPW and other high-powered fancy workflows can make us forget these basics. Anyone who doesn't set good white and black points, whether you, me, Caravaggio, or Monet, will not get satisfactory results. Even after twenty years, IMHO, it's worth a read, regardless of how basic it seems, so I've posted a PDF.

Will people be interested in checking it out? Well, nobody knows what the current situation does to people's psychology. Most of the time now I don't feel inclined to do anything involving color or Photoshop and I suspect others feel the same way. OTOH with so many of us prisoners in our own homes there's a lot of time to study and experiment if so inclined. We've talked about doing some case studies here, where we post a problematic image or two, have members try to correct it, and post and comment on the results. I'm game for it if others are.

Meanwhile, here's the link for the white point column.

And here's the link for all the columns posted so far.

Stay healthy, everybody.

Dan


bill bane
 

Someone has to be the example case of, “…no, that is not quite right….”, and I volunteer to serve in that role. In any case, I would like to try to participate, but I may find myself not up to snuff. It will depend on how fast the fast lane is….

 

Unlike most of the rest of you, I have no color “taste”, with all of mine in my taste buds. I am like the color blind folks that Dan worked with who use numerical stuff to deal with color.

 

I have now finished Dan’s new book. Please accept my previous sentence as it bears on what I am about to say. I found the book enormously useful in trying to build my skills(/”senses”) to think about colors in relation to other colors (hues, tints, or whatever). Unlike most of you, I needed to have a color wheel always by my side as I read the book. From Amazon the “Pocket Color Wheel” uses the same, or close to the same color terminology as Chevreul so I could follow the bouncing ball with complements and “toward its complement”, etc.

 

Like Dan’s other two books, which I had to read three times each, I will need more reading of this book to get these things stuck a bit more in my memory. Actually, I am now pretty sure that my next, the fourth, reading of Dan’s two books will be immeasurably more beneficial as a result of reading this book.

 

As an aside, and as a complement, I do not know what it is about your means of expressing things is, Dan, but I find you to be wonderfully clear. The chapters you took as your own were the best to me, nothing against Mr. C.

 

Like James below, I am an old guy with lots of time, and this was so before this virus thing. Ready to do whatever if and when someone lets me know.

 

Bill

 

From: colortheory@groups.io <colortheory@groups.io> On Behalf Of James Gray
Sent: Sunday, May 03, 2020 4:49 PM
To: colortheory@groups.io
Subject: Re: [colortheory] A column on white point

 

D. Margulis:  Well, nobody knows what the current situation does to people's psychology. Most of the time now I don't feel inclined to do anything involving color or Photoshop and I suspect others feel the same way. OTOH with so many of us prisoners in our own homes there's a lot of time to study and experiment if so inclined. We've talked about doing some case studies here, where we post a problematic image or two, have members try to correct it, and post and comment on the results. I'm game for it if others are.

 

James Gray:  Fortunately for me being confined to my home has not been a lot different from the way my life was before as an old retired guy.  The biggest change is that I do not travel as much and consequently have not taken travel photographs.  I would be very interested in observing or participating in some case studies of problematic images.  In particular I would like to see steps that integrate with the PPW for creating final images that are competitive with or use tools like luminosity masks or ALCE to create the kind of snap, pop, or impact that a lot of images have now in comparison to a dozen years ago.

 

James Gray

 

On Sat, May 2, 2020 at 9:49 AM Dan Margulis via groups.io <dmargulis=aol.com@groups.io> wrote:

Here in New Jersey, for obvious reasons I’ve had a lot of time on my hands and have been using it to clean up some older stuff, including scanning some old magazine columns.

As it happens, twenty years ago I wrote something that because of its very simplicity is potentially more valuable today than it was back then. It’s called “The Great Imaging Equalizer”, and it talks about how the command that we today know as Auto Tone sometimes lets absolute beginners make better corrections than people who consider themselves experts. That leads to a discussion of why it succeeds when it does, why it fails when it doesn’t choose the correct endpoints, and how even an inexperienced person can do better by selecting his own with the eyedropper.

The advent of PPW and other high-powered fancy workflows can make us forget these basics. Anyone who doesn't set good white and black points, whether you, me, Caravaggio, or Monet, will not get satisfactory results. Even after twenty years, IMHO, it's worth a read, regardless of how basic it seems, so I've posted a PDF.

Will people be interested in checking it out? Well, nobody knows what the current situation does to people's psychology. Most of the time now I don't feel inclined to do anything involving color or Photoshop and I suspect others feel the same way. OTOH with so many of us prisoners in our own homes there's a lot of time to study and experiment if so inclined. We've talked about doing some case studies here, where we post a problematic image or two, have members try to correct it, and post and comment on the results. I'm game for it if others are.

Meanwhile, here's the link for the white point column.

And here's the link for all the columns posted so far.

Stay healthy, everybody.

Dan


Dean Wilmot
 

Hi Dan,

Forgive me if this is a basic question esp for this group.

Where in your books does it talk about the best method for setting the black and white points? (for colour and especially B&W images) (and for adjusting mid-tones).

Im starting to use the Howtek 4500 drum scanner I bought last year alot more now and although I've been using a technique recommended by Image Science from the The Fundamentals of Digital e-Book ( section attached) I was wondering though if this is really the best method?

Thanks again 

Regards

Dean Wilmot
Australia


On May 3, 2020 at 4:14 AM, "Dan Margulis via groups.io" <dmargulis@...> wrote:


On May 2, 2020, at 11:59 AM, David Riecks <david@...> wrote:
Dan:
I know of some others who would be interested. Do I have your permission to "reprint" your post above (not just the links) along with suitable attribution? 

Certainly. All posts to this list should be considered in the public domain. Images, no, but text, yes.

Dan Margulis




Dan Margulis
 


On May 3, 2020, at 11:59 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan,

Forgive me if this is a basic question esp for this group.

Where in your books does it talk about the best method for setting the black and white points? (for colour and especially B&W images) (and for adjusting mid-tones).

Im starting to use the Howtek 4500 drum scanner I bought last year alot more now and although I've been using a technique recommended by Image Science from the The Fundamentals of Digital e-Book ( section attached) I was wondering though if this is really the best method?

White point/black point is a subset of the discipline often called “color by the numbers”. Chapter 3 of Modern Photoshop Color Workflow covers this, as does any edition of Professional Photoshop; they all have chapters titled “Color by the Numbers”.

Both approaches try to analyze the image and use curves to eliminate anything that is found to be wrong. Assuming that there is in fact a “white” point and not something very light yet slightly colored, there are two steps: making sure that it is neutral, and making sure that it’s as light as possible consistent with retaining detail.

The traditional approach is to try to accomplish both with a single curve set, and this is what the PP chapters try for. In MCPW the first set of curves must set neutrality only. If convenient, they can also set lightness, but if not the final adjustment is made in LAB. But LAB is clumsy if the file arrives that is not neutrally correct.

Dan Margulis


Dean Wilmot
 

Hi Dan 

Thanks very much mate

I’ll check my various books I have of yours :) 

BTW if you or anyone in the group has a good second hand drum for a howtek 4500 drum scanner please contact me if willing to sell, I’m letting everyone I know I’m interested as. It looks like mine is just starting to craze 😢

Kind regards 

Dean Wilmot


On 6 May 2020, at 02:37, Dan Margulis via groups.io <dmargulis@...> wrote:


On May 3, 2020, at 11:59 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan,

Forgive me if this is a basic question esp for this group.

Where in your books does it talk about the best method for setting the black and white points? (for colour and especially B&W images) (and for adjusting mid-tones).

Im starting to use the Howtek 4500 drum scanner I bought last year alot more now and although I've been using a technique recommended by Image Science from the The Fundamentals of Digital e-Book ( section attached) I was wondering though if this is really the best method?

White point/black point is a subset of the discipline often called “color by the numbers”. Chapter 3 of Modern Photoshop Color Workflow covers this, as does any edition of Professional Photoshop; they all have chapters titled “Color by the Numbers”.

Both approaches try to analyze the image and use curves to eliminate anything that is found to be wrong. Assuming that there is in fact a “white” point and not something very light yet slightly colored, there are two steps: making sure that it is neutral, and making sure that it’s as light as possible consistent with retaining detail.

The traditional approach is to try to accomplish both with a single curve set, and this is what the PP chapters try for. In MCPW the first set of curves must set neutrality only. If convenient, they can also set lightness, but if not the final adjustment is made in LAB. But LAB is clumsy if the file arrives that is not neutrally correct.

Dan Margulis


john c.
 

Just curious, are you using Kami fluid? Lots of people have had that happen who do, including myself.
 
john castronovo
 
 

Sent: Tuesday, May 05, 2020 7:58 PM
Subject: Re: [colortheory] A column on white point
 
Hi Dan 
 
Thanks very much mate
 
I’ll check my various books I have of yours :)
 
BTW if you or anyone in the group has a good second hand drum for a howtek 4500 drum scanner please contact me if willing to sell, I’m letting everyone I know I’m interested as. It looks like mine is just starting to craze 😢
 
Kind regards

Dean Wilmot
 

On 6 May 2020, at 02:37, Dan Margulis via groups.io <dmargulis@...> wrote:


On May 3, 2020, at 11:59 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan,
 
Forgive me if this is a basic question esp for this group.
 
Where in your books does it talk about the best method for setting the black and white points? (for colour and especially B&W images) (and for adjusting mid-tones).
 
Im starting to use the Howtek 4500 drum scanner I bought last year alot more now and although I've been using a technique recommended by Image Science from the The Fundamentals of Digital e-Book ( section attached) I was wondering though if this is really the best method?
 
White point/black point is a subset of the discipline often called “color by the numbers”. Chapter 3 of Modern Photoshop Color Workflow covers this, as does any edition of Professional Photoshop; they all have chapters titled “Color by the Numbers”.
 
Both approaches try to analyze the image and use curves to eliminate anything that is found to be wrong. Assuming that there is in fact a “white” point and not something very light yet slightly colored, there are two steps: making sure that it is neutral, and making sure that it’s as light as possible consistent with retaining detail.
 
The traditional approach is to try to accomplish both with a single curve set, and this is what the PP chapters try for. In MCPW the first set of curves must set neutrality only. If convenient, they can also set lightness, but if not the final adjustment is made in LAB. But LAB is clumsy if the file arrives that is not neutrally correct.
 
Dan Margulis


Dean Wilmot
 

Hi john

No I’m not using kami fluid, I’m
Using Gamsol but I think the problem is the 3m green tape I was using isn’t reacting well. 

I’m going back to Tesa tape with the Gamsol.

Thanks
Regards 

Dean Wilmot
0416 264 230

On 6 May 2020, at 13:22, john c. <jc@...> wrote:


Just curious, are you using Kami fluid? Lots of people have had that happen who do, including myself.
 
john castronovo
 
 
Sent: Tuesday, May 05, 2020 7:58 PM
Subject: Re: [colortheory] A column on white point
 
Hi Dan 
 
Thanks very much mate
 
I’ll check my various books I have of yours :)
 
BTW if you or anyone in the group has a good second hand drum for a howtek 4500 drum scanner please contact me if willing to sell, I’m letting everyone I know I’m interested as. It looks like mine is just starting to craze 😢
 
Kind regards

Dean Wilmot
 

On 6 May 2020, at 02:37, Dan Margulis via groups.io <dmargulis@...> wrote:


On May 3, 2020, at 11:59 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan,
 
Forgive me if this is a basic question esp for this group.
 
Where in your books does it talk about the best method for setting the black and white points? (for colour and especially B&W images) (and for adjusting mid-tones).
 
Im starting to use the Howtek 4500 drum scanner I bought last year alot more now and although I've been using a technique recommended by Image Science from the The Fundamentals of Digital e-Book ( section attached) I was wondering though if this is really the best method?
 
White point/black point is a subset of the discipline often called “color by the numbers”. Chapter 3 of Modern Photoshop Color Workflow covers this, as does any edition of Professional Photoshop; they all have chapters titled “Color by the Numbers”.
 
Both approaches try to analyze the image and use curves to eliminate anything that is found to be wrong. Assuming that there is in fact a “white” point and not something very light yet slightly colored, there are two steps: making sure that it is neutral, and making sure that it’s as light as possible consistent with retaining detail.
 
The traditional approach is to try to accomplish both with a single curve set, and this is what the PP chapters try for. In MCPW the first set of curves must set neutrality only. If convenient, they can also set lightness, but if not the final adjustment is made in LAB. But LAB is clumsy if the file arrives that is not neutrally correct.
 
Dan Margulis


Laurentiu Todie
 

Hi Dean,

I don’t know where you can find the drum you need, but I found this company on eBay.

Maybe they can help.

Good luck!

On May 5, 2020, at 4:58 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan 

Thanks very much mate

I’ll check my various books I have of yours :) 

BTW if you or anyone in the group has a good second hand drum for a howtek 4500 drum scanner please contact me if willing to sell, I’m letting everyone I know I’m interested as. It looks like mine is just starting to craze 😢

Kind regards 

Dean Wilmot


On 6 May 2020, at 02:37, Dan Margulis via groups.io <dmargulis@...> wrote:


On May 3, 2020, at 11:59 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan,

Forgive me if this is a basic question esp for this group.

Where in your books does it talk about the best method for setting the black and white points? (for colour and especially B&W images) (and for adjusting mid-tones).

Im starting to use the Howtek 4500 drum scanner I bought last year alot more now and although I've been using a technique recommended by Image Science from the The Fundamentals of Digital e-Book ( section attached) I was wondering though if this is really the best method?

White point/black point is a subset of the discipline often called “color by the numbers”. Chapter 3 of Modern Photoshop Color Workflow covers this, as does any edition of Professional Photoshop; they all have chapters titled “Color by the Numbers”.

Both approaches try to analyze the image and use curves to eliminate anything that is found to be wrong. Assuming that there is in fact a “white” point and not something very light yet slightly colored, there are two steps: making sure that it is neutral, and making sure that it’s as light as possible consistent with retaining detail.

The traditional approach is to try to accomplish both with a single curve set, and this is what the PP chapters try for. In MCPW the first set of curves must set neutrality only. If convenient, they can also set lightness, but if not the final adjustment is made in LAB. But LAB is clumsy if the file arrives that is not neutrally correct.

Dan Margulis

Laurentiu Todie
DIGITALIS.ART




Dean Wilmot
 

Thanks

I bought the scanner originally off Michael at scan solutions but unfortunately he doesn’t Have any used drums

Regards 

Dean Wilmot
0416 264 230

On 6 May 2020, at 16:25, Laurentiu Todie <todie@...> wrote:

Hi Dean,

I don’t know where you can find the drum you need, but I found this company on eBay.

Maybe they can help.

Good luck!

On May 5, 2020, at 4:58 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan 

Thanks very much mate

I’ll check my various books I have of yours :) 

BTW if you or anyone in the group has a good second hand drum for a howtek 4500 drum scanner please contact me if willing to sell, I’m letting everyone I know I’m interested as. It looks like mine is just starting to craze 😢

Kind regards 

Dean Wilmot


On 6 May 2020, at 02:37, Dan Margulis via groups.io <dmargulis@...> wrote:


On May 3, 2020, at 11:59 PM, Dean Wilmot via groups.io <deanwilmot@...> wrote:

Hi Dan,

Forgive me if this is a basic question esp for this group.

Where in your books does it talk about the best method for setting the black and white points? (for colour and especially B&W images) (and for adjusting mid-tones).

Im starting to use the Howtek 4500 drum scanner I bought last year alot more now and although I've been using a technique recommended by Image Science from the The Fundamentals of Digital e-Book ( section attached) I was wondering though if this is really the best method?

White point/black point is a subset of the discipline often called “color by the numbers”. Chapter 3 of Modern Photoshop Color Workflow covers this, as does any edition of Professional Photoshop; they all have chapters titled “Color by the Numbers”.

Both approaches try to analyze the image and use curves to eliminate anything that is found to be wrong. Assuming that there is in fact a “white” point and not something very light yet slightly colored, there are two steps: making sure that it is neutral, and making sure that it’s as light as possible consistent with retaining detail.

The traditional approach is to try to accomplish both with a single curve set, and this is what the PP chapters try for. In MCPW the first set of curves must set neutrality only. If convenient, they can also set lightness, but if not the final adjustment is made in LAB. But LAB is clumsy if the file arrives that is not neutrally correct.

Dan Margulis

Laurentiu Todie
DIGITALIS.ART




Kenneth Harris
 

re OT: There's a group for drum scanning
scanhi-end@groups.io
Ronsonol+Kami tape works for me.  I've done thousands of scans over 25 years, no crazing.  I think Gamsol's lack of scent leads one to use too much and stay too close to the work. 

Ken Harris


Dean Wilmot
 

Thanks very much Ken

Regards 

Dean Wilmot
0416 264 230

On 7 May 2020, at 02:51, Kenneth Harris <reg@...> wrote:

re OT: There's a group for drum scanning
scanhi-end@groups.io
Ronsonol+Kami tape works for me.  I've done thousands of scans over 25 years, no crazing.  I think Gamsol's lack of scent leads one to use too much and stay too close to the work. 

Ken Harris