4 ms·
Sometimes the goal is just to change the color of an object while retaining the shadows, highlights, and textures. Suppose you had a picture of a blue car and
by mark-r 6y ago
Sometimes the goal is just to change the color of an object while retaining the shadows, highlights, and textures. Suppose you had a picture of a blue car and wanted to know what it would look like in yellow.
- jacobolus 6y agoPersonally I use this tool I built as a Photoshop action over a decade ago, https://www.hcs.harvard.edu/~jrus/colortheory/jl.html https://www.hcs.harvard.edu/~jrus/colortheory/jl.html (see the animation at the bottom showing almost precisely what you are asking about) Initial discussion: https://www.ledet.com/margulis/2010HTM/ACT08-Jacobs_Ladder.htm https://www.ledet.com/margulis/2010HTM/ACT08-Jacobs_Ladder.h... An HSV hue shift (or whatever similar thing you are thinking of) yields horrible results in this use case.
- mark-r 6y agoThat example looks like it's working directly with RGB, which I expect to be correct. I've also seen it work well in HLS. But I worked on a tool where we were told to change from HLS to CIELab because it would be better, and it turned out to be much worse in practice.
- jacobolus 6y agoI almost always use CIELAB as a working color space for photographic work (my action linked previously converts to 16 bit/channel CIELAB space as its first step, though you could use a similar type of tool in RGB mode if you wanted to). But I have a pretty good idea of the final RGB (or other) gamut I am aiming for. Photoshop is definitely designed RGB-first, and some of the tools get a bit clunky in CIELAB mode. It is still an improvement for most of what I want to do. I have many ideas for better image color manipulation tools.