Years ago I was hand building “Step Wedges” with all the tones from 0-255 in grayscale. I would go back to check my work and find that a tone that was supposed to be something like 11 had changed to 12. I contacted Bruce Fraser about this and he told me that “Photoshop is basically a COLOR program and the math is more accurate using RGB values than Grayscale values. So I switched to Adobe 1998 working color space and that solved the problem Best Wishes, Mark Nelson www.PrecisionDigitalNegatives.com <http://www.precisiondigitalnegatives.com/> www.MarkINelsonPhoto.com <http://www.markinelsonphoto.com/> https://rfotofolio.org/mark-nelson/ <https://rfotofolio.org/mark-nelson/>

On Feb 14, 2022, at 2:00 PM, colorsync-users-request@lists.apple.com wrote:

Hi Scott. <snip> Gray again is yet another scale using 0-100%. And no, there is no 0-255 option/conversion.

But my understanding is that Grayscale pixel values are encoded using 0-255. Not 0-100%. If that's true, then surly no math would be required for photoshop to display the 0-255 values? If anything, I imagine math is needed to convert the 0-255 grayscale pixel values to their equivalent ink% values?

And why doesn't photoshop eyedropper display the actual values for grayscale file (i.e. 0-255) when "Actual Color" is selected for the eyedropper? but instead, appears to display those values converted into 'ink % colospace' ?

Or am I missing something again.

Thanks again for your help! Peter Miles