Re: What rendering intent for RGB to CMYK and for proofing on Epson RGB printer?
Re: What rendering intent for RGB to CMYK and for proofing on Epson RGB printer?
- Subject: Re: What rendering intent for RGB to CMYK and for proofing on Epson RGB printer?
- From: Andrew Rodney <email@hidden>
- Date: Wed, 06 Feb 2002 17:04:04 -0700
on 2/6/02 4:47 PM, Marc Levine at email@hidden wrote:
>
However, I think you would agree that when going
>
to a much smaller gamut device (such as an offset press as indicated in the
>
original posting) Relative Colorimetric can deliver unsatisfactory results
>
due to breaks in tonality.
I go by what looks best on screen and to a proof and so far, as I've said,
Relative Colorimetric, ACE and BPC have worked best for *most* images. There
certainly are images where Perceptual will produce superior results. If
someone held a gun to my head and wouldn't allow me to inspect the intent
image by image and pick a single intent, I'd probably still go with Relative
Colorimetric based on the two years of using Photoshop 6 to inspect
conversions. Previous to Photoshop 6, when you couldn't see a soft proof, I
was one that recommended Perceptual "for images," but I've changed that
recommendation.
>
With regards to BPC, it's easy to see that the data is dramatically altered
>
by checking this selection using the eyedropper. I use ICC Tools
>
ProfileViewerPro to check the internal construction of my profiles. You can
>
see that the reported data matches the data in Photoshop with BPC off. Maybe
>
it's just a personal thing, but I like knowing that my profile is the only
>
thing managing my color.
My understanding dating back to Photoshop 5 (and I hope Chris will pipe in)
was that BPC was a fix to a hole in the ICC spec that corrects black
mapping. Some profiles were not producing correct source to destination
black mapping so BPC was a fix. Early after Photoshop 5 was released, I
found one profile manufacturer that had an issue with RGB to RGB conversions
where using BPC caused very muddy black on output. I never saw any issues
with anyone's profiles going from RGB to CMYK. Since then, these guys have
fixed the way they build their RGB profiles so it's moot. So with BPC on,
there really is no harm and in some rare cases, it actually insures proper
mapping from source to destination black mapping. I see no reason not to
simply leave it on all the time.
Andrew Rodney
_______________________________________________
colorsync-users mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/colorsync-users
Do not post admin requests to the list. They will be ignored.