
Isn't it cute?! But then I looked at the prices (follow the links below).
http://store.imatest.com/colorgauge.html
http://www.imagescienceassociates.com/m ... de=TARGETS
Moderators: Chris S., Pau, Beatsy, rjlittlefield, ChrisR
Simply fabulous! I'm thinking about getting a Pico target. I love the calibration data in RGB.Davids wrote:Sometimes I struggle with getting the right colors from my macro work. I know that there are a number of products available, such as the x-rite color checker, that allow you to create an accurate color profile for the scene being imaged. But how could I use something like that for my macro work? Well, I found an answer, albeit an expensive one (isn't that usually the case?).
Isn't it cute?! But then I looked at the prices (follow the links below).
http://store.imatest.com/colorgauge.html
http://www.imagescienceassociates.com/m ... de=TARGETS
I'll posit as follows:ray_parkhurst wrote:Can anyone posit why the patch 7 R channel in sRGB is -49?
I have not studied this particular case.Chris S. wrote:I'll posit as follows:ray_parkhurst wrote:Can anyone posit why the patch 7 R channel in sRGB is -49?
Note in the explanatory comments of the spreadsheet: "The count values shown in RED below are considered out-of-gamut for the particular color space listed." (Emphasis theirs.)
That depends on the definition of "should".This makes sense, but the sRGB values are invalid. I would still assume the value should be 0 in sRGB space.
For patch 7, the spreadsheet quotes the Lab values as (50.86,-27.78,-27.68 ). Running those values through the CIE Color Calculator at http://www.brucelindbloom.com, and scaling to 0..255 like PhotoShop does, I get sRGB values (-48.87,135.35,167.58 ), nicely reproducing the spreadsheet's (-49,135,168). So, I'm pretty confident about the interpretation.The RGB calculations for a given Color space condition were calculated from formulas at http://www.brucelindbloom.com
RGB values for other color spaces can be calculated by visiting the above URL.
I take a blurred picture of each patch with a 4x objective under a D50 (5000K) light, then I manually merge them in a single grid picture.Davids wrote: ↑Thu Jan 10, 2019 9:01 amPardon my ignorance, but how would you use the target to create a profile within lightroom? For example, something like x-rite color checker has it's own Lightroom plugin that can recognize the target in an image and create a profile for that photograph.
I contacted x-rite and they said that their software is not compatible with these smaller targets.