Message
Re: [colorvision_group] Saturation or Perceptual?
2007-05-29 by CDTobie@aol.com
In a message dated 5/28/07 10:34:57 PM, tom.husband@... writes:
The default in Qimage when printing is perceptual. I use PFP2
profiles but I'm confused when C. David Tobie said, "Saturation intent
is highly recommended, though intent choice will vary with different
subject matter and other factors." I thought saturation was for
charts and graphs and perceptual was for photographs.
I guess I missed that in the users guide too.
Intents are what the color management developer makes them. So those who define intents according to the oft repeated folklore about what intents are "supposed" to be, are missing the point. Ask the people that create them, if you want to know what they are and how they work. In the case of ColorVision intents, saturation biases out of gamut colors to the more saturatated gamut-edge colors that could be used, which is often exactly what people want from such bright, unprintable, colors. In other instances, the perceptual, or even the colorimetric, intent may serve more effectively. But if you are using ColorVision generated profiles and looking for saturated colors in your work, and you haven't tried the saturation intent, you are definintely missing a big opportunity.
Lets take a New York Taxi as an example. We all know that tone of saturated sunflower yellow, and those of us who print a lot know that some inksets can't even get close; they have a weak, lemony yellow primary. So when you print a NYC street shot, what color do you want for your cabs? Do you want them to be the closest colorimetric equivalent, meaning lowest difference in Hue, Saturation, and Brightness? With many inks that will be a dull tone that does not say "NYtaxi" to me. How about Perceptual? That will be the in between result, with a bit brighter, but less literal, yellows. The Saturation intent will sock you in the eye with saturated yellow, but it will be ink tank yellow, so whether it has that NYtaxi look or not will depend on what inkset you are using. This is why I say your intent choice may vary with the subject matter, or other factors... like your inkset, and the paper you are printing on.
And beyond the "let the intent do it" choices, is the option to bring that yellow into gamut yourself, in Photoshop, SoftProofed to the printer profile, and using the gamut warning to let you know when you are getting the yellows to a printable range. Then its not the intent defining your colors, its you. Keep in mind that your MONITOR is weak in yellows, and that you may want to SoftProof to your monitor profile as well, to check that the colors you are adjusting visually on screen, are actually representable on screen!
So its never so simple as saying "I use the blah blah blah intent because its best"... its all, pardon the pun, relative.
C. David Tobie
Product Technology Manager
ColorVision Business Unit
Datacolor Inc.
CDTobie@...
www.colorvision.com
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