Re: There is no place for individual taste in screen appearance.
John Robert Robinson, something we still need to clear up is your assertion that your are measuring some color. If you are using the eye-dropper in Photoshop or any of the other cursors, you are not measuring anything. The cursor is simply reporting a number derived from the opened file. The numbers mean nothing without a profile. The ICC color profile provides the definition for the numbers. The document needs a profile to define the “colors” and Photoshop needs to reference that through a profile that describes or characterizes the display. All RGB profiles use a scale of numbers from 0 to 255 but ProPhoto can produce saturated colors that sRGB never could. The scale is different, the distance from the center to the edge is greater, and the further from the center, the more saturated the color. ProPhoto is larger, sRGB is much smaller and their shapes differ. The center is always zero and the edge is always 255. Color is 3 dimensional and the shape varies from one profile to another. The top at the center is white and the bottom at the center is black. That’s why we convert from one color space to another - to preserve the color appearance on some other device. This is the only time a profile becomes active because the conversion does change the numbers but preserves the appearance. Assigning changes the appearance but not the numbers. Seems counterintuitive but its not when you understand the size and shape of color profiles. I had to chuckle at John Gnaegy’s use of “salmon” as a color reference for I was coming up with a very similar example. To illustrate this, create a new RGB document in Photoshop, make it sRGB. Go to the color picker and make a new RGB color using R255, G128, B128. Fill your new document with that salmon color. Now go to Edit > Assign Profile, and make sure the Preview check box is selected. Assign ProPhoto, you will see the color change to “Magenta.” Now assign ColorMatch RGB and you will see the color shift to a washed out version of “Salmon.” If you also had your info palette open when doing the Assign Profile, you would also notice that the numbers did not change at all, just the appearance. The numbers by themselves mean nothing. The color profile is paramount in providing definition to the numbers. Also when using the eye-dropper in Photoshop to report on the numbers, and especially when checking the cleanness of the whites - avoid the use of Point Sample, which is a single pixel. Use a 3x3 matrix, the average of nine pixels, or use 5x5 the average of 25 pixels, that will give you a much better representation of any tint your whites may have. David Wollmann
What role does coffee have in perception of color? Do other legitimate prescription or over the counter items have a role in color prerception. Cheers David David B Miller, Pharm. D. member Millers' Photography L.L.C. dba Spinnaker Photo Imaging Center Bellingham, WA www.spinnakerphotoimagingcenter.com 360 739 2826
Caffeine can affect various parts of your body. In some, even moderate consumption can cause blood sugar to rise or drop, resulting in blurred vision. My point was we are biological and the things we consume can have an affect on how we function and perceive. The eye has an incredible ability to adapt and fool us in to thinking we are seeing something that is not so, such as the MIT Checker Board example. Also, there is chromatic adaption, color constancy, or discounting the illuminant, an example is the use of a tungsten light bulb. This type of light is very warm from say 2800K to 3200K and yet we see it as white light. If you shoot daylight film however with tungsten light, the result is a very warm photograph. Our eyes are very good at making comparisons, two prints side by side, but lousy at determining absolutes and calibrating a display is about absolutes. My feeling is that if you conform to standards for your display and your image looks the way you want it to, then it has a fighting chance of looking decent on some other display that is uncalibrated. At least it should’t exaggerate an unwanted color cast because you are starting from a known condition that is, shall we say, “neutral.” David Wollmann On Jun 9, 2014, at 10:00 AM, Millers' Photography L.L.C. <digitalimaging@dnmillerphoto.com> wrote:
What role does coffee have in perception of color?
Do other legitimate prescription or over the counter items have a role in color prerception.
Cheers
David David B Miller, Pharm. D.
Agreed. When I introduced the enlargers (4x5)’s, to the brick and mortar store we once had, I did the printing. My employees said my colors were off. WAY off. They were all correct. Machine printing is all they knew. And they were all excellent! Today, all digital. Point is, me. I am not good at noticing slight changes in color. Wondered if, for me, coffee did or did not make a difference. I make previews, proofs, or whatever one wants to label them, and client tells me what to change in the colors. Cheers David On Jun 9, 2014, at 11:08 AM, David Wollmann <david@lenzart.us> wrote:
Caffeine can affect various parts of your body. In some, even moderate consumption can cause blood sugar to rise or drop, resulting in blurred vision. My point was we are biological and the things we consume can have an affect on how we function and perceive.
The eye has an incredible ability to adapt and fool us in to thinking we are seeing something that is not so, such as the MIT Checker Board example. Also, there is chromatic adaption, color constancy, or discounting the illuminant, an example is the use of a tungsten light bulb. This type of light is very warm from say 2800K to 3200K and yet we see it as white light. If you shoot daylight film however with tungsten light, the result is a very warm photograph.
Our eyes are very good at making comparisons, two prints side by side, but lousy at determining absolutes and calibrating a display is about absolutes.
My feeling is that if you conform to standards for your display and your image looks the way you want it to, then it has a fighting chance of looking decent on some other display that is uncalibrated. At least it should’t exaggerate an unwanted color cast because you are starting from a known condition that is, shall we say, “neutral.”
David Wollmann
On Jun 9, 2014, at 10:00 AM, Millers' Photography L.L.C. <digitalimaging@dnmillerphoto.com> wrote:
What role does coffee have in perception of color?
Do other legitimate prescription or over the counter items have a role in color prerception.
Cheers
David David B Miller, Pharm. D.
On Jun 9, 2014, at 11:08 AM, David Wollmann <david@lenzart.us> wrote:
Also, there is chromatic adaption, color constancy, or discounting the illuminant
My favorite way to demonstrate this is with the following experiment: on a sunny day, step outside into the Sun. Close both eyes, and also cover only one eye with the palm of your hand. While keeping both eyes closed (Warning: Do not stare at the Sun with remaining eye!), turn your face full upon the Sun, and stay like that for a minute or so. Then, turn your face away from the Sun, and compare the way the world looks in each eye. Which eye is seeing the world correctly? b&
The one that survive. ;-) 2014-06-10 19:50 GMT+01:00 Ben Goren <ben@trumpetpower.com>:
On Jun 9, 2014, at 11:08 AM, David Wollmann <david@lenzart.us> wrote:
Also, there is chromatic adaption, color constancy, or discounting the illuminant
My favorite way to demonstrate this is with the following experiment: on a sunny day, step outside into the Sun. Close both eyes, and also cover only one eye with the palm of your hand. While keeping both eyes closed (Warning: Do not stare at the Sun with remaining eye!), turn your face full upon the Sun, and stay like that for a minute or so. Then, turn your face away from the Sun, and compare the way the world looks in each eye.
Which eye is seeing the world correctly?
b&
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participants (4)
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Ben Goren
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David Wollmann
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José Ángel Bueno García
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Millers' Photography L.L.C.