On samedi 4 février 2017 09:03:18 CET Michael Below wrote: > Hey, > just a quick note about the basecurve: that curve is very early in the > processing stack. So if you blow your highlights in this stage, they are > gone, before you can do something about it. If there are exposure problems > it is far better to use the contrast curve in the colour tab, because that > is applied later. Cheers > Michael
Yes and no. Note that I said it was not very useful to disable the basecurve *if you are going to enable it again later*. In DT, modules are applied in a fixed order, independant of when you activate them. In addition, DT works internally in 32- bit floating point, and does not clamp the colour values within the pipeline (that's what the developers tell us, anyway: see section 3.2 in the manual). Of course, colour values *are* clamped to a fixed range at the end of the treatment (if only because you don't want values to wrap around when going to 8 bit/channel), but that's not relevant in selecting which modules to use. That is not to say that picking another basecurve to spare your highlights can't be useful, but this *will* influence the whole image, just like the tone curve. That was something the OP wanted to avoid. And that requirement means you will have to use some form of masking. I find that parametric masks can work rather well in such circumstances. And don't forget that, in general, you will want to apply a rather aggressive S-curve to transform your sensor data (intensity linear with photon count) to something pleasing for you (intensity ~logarithmic with photon count). You have a choice of using one of the provided basecurves (optimised to reflect the basic style of different camera brands) or build your own in the tonecurve module. Remco ____________________________________________________________________________ darktable user mailing list to unsubscribe send a mail to darktable-user+unsubscr...@lists.darktable.org
