April 2020 - colorsync-users

Re: Humans (and cameras and scanners) do not have a color gamut (?)
by Rich Wagner 19 Oct '20

19 Oct '20

I agree with Florian’s responses below regarding how we “know” what animals “see.” The parallel question is how we “know” what women with tetrachromatic vision “see.” There is a very good article from the BBC that describes this that might help. https://www.bbc.com/future/article/20140905-the-women-with-super-human-visi… Here’s a short excerpt from the excellent story: Proving that these people actually see the world differently has involved a two-decade journey, however. Although the relevant combination of genes does not seem to be especially rare – perhaps 12% of women might have four distinct cones – many of the people that Jordan tested just didn’t seem to show any differences in their perception. But by 2010, she had found a subject who perfectly acted the part of a tetrachromat. Jordan’s “acid test” involved coloured discs showing different mixtures of pigment, such as a green made of yellow and blue. The mixtures were too subtle for most people to notice: almost all people would see the same shade of olive green, but each combination should give out a subtly different spectrum of light that would be perceptible to someone with a fourth cone. Sure enough, Jordan’s subject was able to differentiate between the different mixtures each time <http://www.journalofvision.org/content/10/8/12.full>. “When you ask them to discriminate between the two mixtures, a tetrachromat can do it very quickly. They don’t hesitate,” says Jordan. Unfortunately, much of the research in color perception is highly complex and often difficult for the lay public to comprehend. Good science writers can translate that research into language the lay public can understand. Poor science writing leads to exaggerated claims and misinformation. That said, the title of this article is a bit over the top. I don’t think these women have “super human vision” any more than those who are colorblind have “sub human vision.” Both have visual perception that is significantly different from the average of our species. —Rich > OnMon, 13 Jan 2020 19:40:11 +0100, Florian Hoech <lists+colorsync-users(a)hoech.org <mailto:lists+colorsync-users@hoech.org>> wrote: > [snip] >> Not a single case can be made by anyone?s fisthand information about the post processing by the brains of these animals. Who can know what they see or apprehend? > > You can draw pretty useful conclusions (meaning they work well in > real-life, thus supporting the respective theories) from all the > scientific research that has been done. "Color" perception is not just > "nice to have". Trichromats (like humans) have an evolutionary edge over > (say) dichromats, e.g. when it comes to distinguish edible/nutritious > from inedible/less nutritious food like fruits etc. When you look at the > M and L cone responses of any trichromat, you can see that the responses > of the "sensors" (cones) largely overlap. Yet, we seem to perceive the > "end result", green and red, as very different colors (opposites even!). > >> Since humans communicate with each other about color we can build models and references and so on. But animals? Yet, experts are quick to supply examples of how things must appear to non-humans. > > I think you may be conflating the actual research with how it is > presented (usually not by the researchers themselves), broken down and > simplified in newspapers/magazines/articles, online and offline, meant > for consumption by the general public. > >> When we grant that all of these theories are onto something about the ways animals percieve color we account for their differences by describing them in terms of ?gamuts?. > > I like the term "dimensions". A Tetrachromat has an additional dimension > of "color". > >> Surprise: experts determine gamuts based on the sensor alone! They don?t even seem to be the slightest bit unhappy about it. > > ...where? And who? Dimensionality alone doesn't really tell us much > about gamuts. > > Florian. >

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RE: Influencing Software Development
by graxx＠videotron.ca 28 Apr '20

28 Apr '20

Do they have small introductory videos on YouTube? Simple application demos? Any chance Argyll will support this instrument? Is it available in North America? MfG / Roger -----Original Message----- From: Claas Bickeböller via colorsync-users <colorsync-users(a)lists.apple.com> Sent: Tuesday, April 28, 2020 2:51 AM To: Colorsynclist <colorsync-users(a)lists.apple.com> Subject: Influencing Software Development Dear users of color management software, please take the opportunity to give feedback which features you want to see in a color management software. At the bottom you'll find a short survey. https://www.myiro.com/MYIROtools Best regards Claas _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca This email sent to graxx(a)videotron.ca

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Influencing Software Development
by Claas Bickeböller 28 Apr '20

28 Apr '20

Dear users of color management software, please take the opportunity to give feedback which features you want to see in a color management software. At the bottom you'll find a short survey. https://www.myiro.com/MYIROtools Best regards Claas

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Color differences
by graxx＠videotron.ca 09 Apr '20

09 Apr '20

I am given two sets of CIE Lab numbers, [ Reference: 50 40 40 ] and [ Sample: 50 34.25 45 ]. Between the two sets of numbers, I find 4.89 DE00 color difference. My question is this, Is 4.89 the 'Total difference'? As you may know, DE00 tolerances generally take the form of 'ellipses' (neutrals are more 'round', I'm told). Picture a typical ellipse, it has a 'Major axis' (width) and a "Minor axis' (height). The Major axis is the longer dimension of the two. Suppose the center of the ellipse is the Reference color above, is 4.89 to be considered the 'width' of the entire length of Major axis or is it twice the 'width', 4.89 on each 'side' of the center? I'm pretty sure I know the answer but I'm running into what seems like a huge visual difference between the two sets of numbers and I want to be sure I'm not making a mistake in my interpretation of the DE00 difference. / Roger Breton www.graxx.ca

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Does your research enhance the study of color science?
by Roberta Morehouse 02 Apr '20

02 Apr '20

Does your research enhance the study of color science or impact applications like virtual reality, 3D Printing, cinema, video, or computer vision? Consider sharing your expertise as an oral or interactive paper. There’s still time to submit your research, but it’s running out! Learn more at http://bit.ly/CIC28_ CIC28 | November 2-6, 2020 | Chiba, Japan In conjunction with Printing for Fabrication (Print4Fab) http://bit.ly/CIC28_ DEADLINES Conference Paper: 26 April 2020 Final Manuscript: 7 September 2020 CIC28 Call for Papers - http://bit.ly/CIC28_CFP Direct submission inquiries to Katrina Bird @ cic-papers(a)imaging.org Connect with our community! Twitter @ImagingOrg #CIC28 IS&T LinkedIn Groups: imaging.org, color and imaging (CIC), archiving (Archiving), & digital printing (Printing for Fabrication)

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