Mon Jan 23, 2023 9:17 am
- When you are in 8-bit integer, the display uses the legacy 0-255 range, but in other cases it uses a 0-100% range (with decimals...) (because using the actual 0-1 range could be seen as a bit too technical for most).
Mon Jan 23, 2023 9:27 am
Mon Jan 23, 2023 11:54 am
Mon Jan 23, 2023 12:29 pm
Mon Jan 23, 2023 1:38 pm
Mon Jan 23, 2023 8:25 pm
gramp wrote:Thanks, Ofnuts.
It has the feel of an oversight to me, in the sense that in 8-bit mode, I can specify any and all of the 8-bit colors in the palette, but in 16-bit mode? ...I can specify any and all of, only, the 8-bit colors in the palette.
I'm now wondering if I can paint a layer with a 0->100% gradient (will it contain more than 255 grays?)[1] and select foreground and background colors from that layer with the color-picker tool which are have values other than in the range 1->255.[2]
[3]
[1] Well, first off, the image would have to be at least 255 pixels in one direction (up, down, diag) in order to have containers for at least 255 grays. (I just tried creating an image of 65535 px square; machine joined GIMP in a hearty laugh indeed.)
[2] I realize that I must have at least access to 1000 gray levels as my L slider admits 1 decimal point of precision; I can set values from 1.0 to 100.0 in 0.1 increments. In connection with [1] looking for or expecting 65535 gray levels for the few-thousand-pixels-per-side models I do is probably pollyannish.
[3] The problem for me is that when I stroke a heightmap with a gradient and then try to cut it out with a CNC there are discernible "steps" between gray levels in the final product, smoothed or not. I know "there are limits" to digital processing, but I'd sure like to know where they might be.
Mon Jan 23, 2023 10:13 pm
Mon Jan 23, 2023 10:30 pm
ofnuts wrote:You are mistaking Gimp for an array calculator. Nobody thinks of the colors or the luminosity levels in terms of 16-bit numbers. So it's not an oversight, it is a balance between usefulness for the intended users and code maintenance.
[2]level is 1-100 by .01, so that's 10K levels.
[3]First off, make sure that there is no dithering/super-sampling in the gradients, or, if there is, that it plays in your direction. With dithering I would expect a slightly grainy surface, and without there would be smooth areas with steps in between.