Very welcome. I hadn’t seen the documentation saying it automatically down samples to 500 pixels. I see that now, and agree that part is documented.
As long as it used a downsampling method that chose pixel values that were actually in the original image, that would be fine with me. Nearest neighbor, or something to that effect.
It’s not doing that though, it’s using downsampling that creates new RGB values.
If you see a previous post I made at [url]http://one.imports.literateforums.com/t/colors-expand-converting-from-printer-profile-to-prophotorgb/1008/8] about “Colors expanding converting from printer profile to ProPhotoRGB”, which I now know is caused by the resampling method chosen, that perfectly illustrates the problem with using a downsampling method that tries to make the image look nicer.
All of the pixels in graph 3 in that post should be in gamut of the printer profile, but are massively expanded outside of it.