On 1/11/13 12:55 PM, Robert William Hutton wrote: > Sounds to me like what you really want to do is raise the gamma > rather than raise the exposure.
Gamma is a non-linear modification that has no equivalent in real world photography. Exposure is a well understood concept (multiplication with a fixed number) that maps directly to the real world. Then you want to manipulate the full tonal range of the resulting image, possibly bringing parts that were pushed >1.0 back into to 0..1 range to recover detail. Of course, you can partly express this with a gamma curve, that is: anything that was shifted outside 0..1 and the brought back into that range. But if you want to keep 5% of your pixels still overexposed gamma won't let you do this. Lastly, it is anything but intuitive, in the OP's use case. Furthermore, when you want to work on parts of the tonal range and leave the rest absolutely fixed, you need a lot of points on the tone curve and it becomes fiddly and unintuitive. I think the (between the lines) feature request of the OP is to extend the working tonal range of the highlights/shadows module, by a certain % or automagically, to the highest value present in the image. So for highlight recovery, there would be modes of working: - Normal (current code, clips at 1.0, no way to recover values pushed outside that range by previous modules in the pipe or present in the original image) - Auto (highlight tonal region extends beyond 1.0, to highest value in image) - Extended (user defined % of values above 1.0 becomes part of highlights tonal range, i.e. 80% means highlights can go up to 1.8, etc. Maybe this needs to be a an exponential slider, instead of % though) Does that make sense. .mm ------------------------------------------------------------------------------ Android is increasing in popularity, but the open development platform that developers love is also attractive to malware creators. Download this white paper to learn more about secure code signing practices that can help keep Android apps secure. http://pubads.g.doubleclick.net/gampad/clk?id=65839951&iu=/4140/ostg.clktrk _______________________________________________ darktable-devel mailing list darktable-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/darktable-devel
