Re: offlist: this editing space debate on CS user
Re: offlist: this editing space debate on CS user
- Subject: Re: offlist: this editing space debate on CS user
- From: bruce fraser <email@hidden>
- Date: Mon, 25 Nov 2002 09:40:18 -0800
At 10:20 AM -0700 11/25/02, Chris Murphy wrote:
Bruce writes:
In fairness to Don, the Fuji, while it has a fairly large gamut,
doesn't go anywhere near as far into the yellows and oranges as a
good sheetfed press, and it also is a tad lacking in saturated
greens. If you compare the Fuji profile with Thomas Knoll's US
Sheetfed Coated v2 in ColorThink, you'll see the fairly obvious
mismatch. If you then overlay Adobe and Don or Best RGB, you'll see
that these are exactly the areas that Don and Best include and that
Adobe clips.
I've just done some 3D modeling with ColorThink 2 comparing Adobe
RGB (1998) to both SWOP and Sheetfed Coated v2.
The model shows Adobe RGB (1998) completely containing U.S. Web
Coated (SWOP) v2. Not even a little is out of the Adobe RGB gamut.
It shows a small squeak of a slice of yellow-orange as being
reproducible on U.S. Sheetfed Coated v2, but not in Adobe RGB
(1998). The model indicates Adobe RGB is very close to the gamut
boundary of Sheetfed Coated v2, but has lots of headroom on all of
the other colors. If the model is accurate, I find it impossible to
believe that an RGB editing space bigger than Adobe RGB would
provide any practical benefit.
The model is presumably based on relative colorimetric rendering.
What might this show for perceptual rendering, where the effectively
gamut volume of a device is expanded (beyond it's true gamut)? I'm
not sure, but perhaps here there would be a more noticable benefit
of some other editing space in this case, but right now I'm just not
seeing it.
Chris Murphy
Color Remedies (tm)
Boulder, CO
www.colorremedies.com
I've certainly captured colors that lie in that small squeak of
yellow-orange. It's not unreasonable to suppose I might want to
reproduce them.
Perceptual rendering doesn't do anything to the gamut boundary --
that's a fixed analog limitation.
And I wouldn't take US Sheetfed Coated v.2.0, good though it is, as
the canonical definition of what can be acheived on sheetfed press
with coated stock.
It's undoubtedly true that for people whose only concern is press
output, the vast majority will see no practical benefit, on press
output, from an editing space larger than Adobe RGB. It's a big
stretch to go from that to "there's no practical benefit to an
editing space larger than Adobe RGB."
B
--
email@hidden
_______________________________________________
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.