Re: Rel vs Abs proofs
Re: Rel vs Abs proofs
- Subject: Re: Rel vs Abs proofs
- From: Marco Ugolini <email@hidden>
- Date: Thu, 12 Oct 2006 14:11:00 -0700
In a message dated 10/12/06 1:05 AM, Rick Gordon wrote:
> Although I see a general preference for the AbsCol rendering for proofing in
> this discussion, don't you find that some people just don't warm up to a pure
> "white" that is registered with ink on the paper? I know for myself, I like to
> see clipped areas showing as pure paper with no ink on it, and feel that the
> variance in paper tone is less of a problem than the appearance of ink in pure
> whites.
>
> Also, since you can't attain a value lighter than the paper, even setting
> accurate a and b values will not accurately simulate a printing stock with a
> higher L value than the proofing stock.
>
> That being the case, might there not be a case to be made for a hybrid
> colorimetric rendering that is essentially AbsCol except for pure whites, but
> pure white where c0,m0,y0,k0 (or R255,G255,B255) exists in the file? I would
> assume that, if you are converting prior to printing, a blend-if layering of a
> AbsCol and a RelCol rendering, where the AbsCol would be visible if the value
> on RelCol layer is 0 to 254.
>
> And also, might a case made for a range of proofing stocks targeted
> specifically to various standard (or common) press stocks?
A few brief observations regarding this discussion (which seems to be
getting more and more convoluted and confusing as it moves along):
1) The whole purpose of the Absolute Colorimetric rendering intent is to
simulate the effect created by the substrate on which an image will be
printed (on a printing press), effect which will determine both the white
point (obviously) and other colors throughout the image (to varying
degrees). And, of course, in order to do this, the paper on which the proof
is done has to have an L* value equal or higher than the final stock. So,
pray tell, how is it supposed to make our proof any better, or more
dependable, if we print it without simulating the white point of the final
stock?
2) One other thing is also not clear to me: are we assuming that when we
produce the proof we are *trimming* its edges, so that the whitest point in
the proof is the *simulated* white of the proof and not the white *of the
paper itself* visible in those edge areas that are not covered by any ink?
If you trim your proofs, the eye adapts fairly quickly to the proof's
simulated white point, and the average client will probably never make an
issue of it unless *you* are foolish enough to point it out to him/her.
3) Call me not the brightest bulb in the room if you please, but isn't "a
hybrid colorimetric rendering that is essentially AbsCol except for pure
whites" what we already call Relative Colorimetric? And if by "hybrid" you
mean an intent that simulates the effect of the substrate on the whole image
except pure whites, why would you provide your client with a proof
exhibiting a degree of contrast that is higher than what can be matched on
press?
Regards.
--------------
Marco Ugolini
Mill Valley, CA
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden