Yes, there is not much in the way of "quantifiable" ways to evaluate printer profiles. But I really like the idea of viewing the rendered gamut in ColorThink Pro: http://www.youtube.com/watch?v=sTxaHhMYSYE This is a visual means of comparing profiles, but it's really quite illuminating and gives you clear, objective reasons for preferring one profile engine over another. This video talks about checking the smoothness of the rendering, and shows how you can see if the rendering of out of gamut colors is making the most use of the printer's total ability to print. Pat Herold
From: Roger Breton <graxx@videotron.ca> Date: May 3, 2013 3:46:42 AM PDT To: 'LdaSignup' <ldasignup@gmail.com>, "''colorsync-users?lists.apple.com' List'" <colorsync-users@lists.apple.com> Subject: RE: HowTo? Objectively measure quality of print profiles?
Dear LdaSignup,
The test of Output Profiles can be arduous and not necessarily reducible to simple colorimetric accuracy.
The iSis or some other automated instrument -- I'm still fond of my Spectroscan tables -- can and should be used to assess the colorimetric accuracy for proofing but no more. The rest, the appearance of neutrals, the rendering of skintones and other memory colors should be done visually. For what it's worth, I am a die-hard ColorChecker user, I like checking the accuracy of the colorimetric table of my Output Profiles with a custom measured chart. It's fast, simple, not too many samples and the samples are large enough to have a good stab at visual comparison between the original and its reproduction. Heck! Everyone should have a ColorChecker chart on its shelves -- thank you so much Cal McCamy! BTW, have you ever seen the ColorChecker made up of yarn that they have at the Munsell Institute of Color Science, in Rochester? Wow...
Best / Roger
-----Original Message----- From: colorsync-users-bounces+graxx=videotron.ca@lists.apple.com [mailto:colorsync-users-bounces+graxx=videotron.ca@lists.apple.com] On Behalf Of LdaSignup Sent: Thursday, May 2, 2013 8:29 PM To: 'colorsync-users?lists.apple.com' List Subject: HowTo? Objectively measure quality of print profiles?
Starting a new thread to avoid hijacking another, unrelated thread about picking a camera ...
I'm very curious how Andrew Rooney (aka "The Digital Dog") tests/evaluates the quality of profiles.
Everything was visual. Lots and lots of real world and synthetic images. Some of Bill Atkinson's test images are wonderful (28 Balls). The 28 Balls image is a ball breaker and shows a lot about the color engines. The Roman 16's are always used.
Is this test/evaluation something that a well calibrated X-rite i1iSis could do "by the numbers" with "apples and apples" De2k's using the X-Rite MeasureTool's Compare freeware (2.0.# on a PC, 1.5.# on a Mac)?
Hypothetically, suppose someone claimed that profiles from ArgyllCms are typically as good or better than those from ProfileMaker-5, and almost as good as i1Profiler 1.4.2. Is that something that could be objectively measured by an automated spectro, rather than an informed, but still subjective, opinion?
* Could there be some kind of weighted "figure of merit" of, for example, De2k + Adjusted-Gamut-Volume?
* Are De2k accuracy + gamut-volume the primary considerations when evaluating profile quality? What else? Banding? Is there a way to measure that, and reduce to a number grade by a machine?