Re: JPEG's


Andrew Engelhardt
 

Oh man, another ICC thread. I thought Colorsync was the place for this
malarkey, but since it's been brought up yet again, let me ask you a
question Andrew. Have you ever worked in a high volume print production
environment? Judging from your presumptuous statements about storage space
and archiving files I'd assume not. The department I work in has several
different "working" archives of files (as opposed to the several thousand
files we must store off-line), the largest currently consisting of approx
50,000 images. On top of this we have hundreds and hundreds of other image
files of varying size, type, and purpose. Let's say the average ICC profile
comes in around a "mere" 700k - you do the math for just that one archive.
As part of my job as the "archivist" I have to keep storage space within
reasonable limits - it's not THAT cheap. Adding 500k-1.5Mb per file is not a
reasonable trade-off for the amount of "useful" information an ICC profile
carries which in the end will most likely be ignored anyway. I'd be better
off attaching a text document to each file describing all the CMYK specs
contained within. I deal with hundreds of CMYK images each week, and adding
a profile is just not practical. Secondly, RGB is NOT always best for
sharing or archiving files nor is it easier to re-purpose. In some cases
yes, but on the whole I'd disagree with this claim. Storing files in CMYK
means color-correction/contrast adjustments/out of gamut colors etc have
been dealt with (or should be) - who wants to do it over and over? For these
reasons alone it's easier to re-purpose a CYMK for other use. Anyway, that's
just my opinion of course, but what do I know?....

A. Engelhardt

-----Original Message-----
From: Andrew Rodney [mailto:andrew@digitaldog.net]
Sent: Tuesday, November 26, 2002 6:36 AM
To: colortheory@yahoogroups.com; john c.
Subject: Re: [colortheory] JPEG's


on 11/26/02 6:56 AM, john c. at jcc@nac.net wrote:

As for sharing and archiving files, RGB is always best because it's
smaller,
has more information and is easier to re-purpose. CMYK is required for one
purpose only: the printing press, and if that is your only desire, then by
all means use it and throw the rest of the information away for good.
Amen brother!

To do
a good job however, we shouldn't separate to CMYK without a thorough
knowledge of the printing conditions including paper stock. That's not
always possible, so I prefer to send tagged RGB files *and* a tagged CMYK
file if I can't get the information I need. If space is the major concern
(as it was in this question), I'd prefer tagged RGB to untagged CMYK, the
latter being really reckless without a proof.
Again, I agree. I¹ve never seen an ICC profile bigger than a meg and half
and most come in at 500K or so (for output profiles; Working Space and
display profiles are tiny). The space issue isn¹t going to fly with me
UNLESS you¹re talking images for the web where we need the smallest files
possible. And unless a user is running Microsoft IE 4.5 or 5.0, the web
isn't¹ color managed anyway (with IE it certainly is and produces previews
just like good old Photoshop).

With the cost of storage and more and more digital cameras producing files
starting at 18mb and going up, what¹s a mere 500K? I suppose all the people
that worry about file size and profiles never save layers and JPEG all their
archives using 30:1 ratio. Those files and small!

Andrew Rodney


[Non-text portions of this message have been removed]



To unsubscribe from this group, send an email to:
colortheory-unsubscribe@yahoogroups.com



Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/




[Non-text portions of this message have been removed]

Join colortheory@groups.io to automatically receive all group messages.