Something that I now find that is more effective is the use of the channel-mixer along with blentif. I also am using the lightness tab to select the brightest pixels and then I pull the red values slightly back which gives the blue values a chance to be seen.
I have however become a lot more cognicent of the problem during the shooting session in an effort not to have to deal with this situation later on. David On 13-06-03 09:07 AM, Rob Z. Smith wrote: > An easy way to bring down the brightest pixels in a controlled way is to just > use the Graduated ND filter setting the blendif parameters in the lightness > tab to only hit the brightest pixels. That will let you set exactly the range > of brightness you want pulled down and how sharp a transition you want. i.e. > it can be done without mucking up the rest of the image. > > > -----Original Message----- > From: Chris Siebenmann [mailto:c...@cs.toronto.edu] > Sent: 28 May 2013 22:43 > To: darktable-users@lists.sourceforge.net > Cc: c...@cs.toronto.edu > Subject: [Darktable-users] Best way to recover highlights that are blown in > processing? > > A number of darktable processing steps can push unclipped RAW channels into > overexposure under some circumstances (for example, the standard Nikon base > curve not infrequently blows highlights out on me). As a relative beginner at > darktable, I'm interested in people's views on the best and easiest way to > recover the highlights in this case. > > I think that what I want at a conceptual level is to pull the highlights > down (I assume inevitably reducing highlight contrast), but there may be > something that gives a better visual look. Things I've tried, without > universal success: > > * the Shadows and Highlights module often doesn't really reduce the > blown highlights very much (or at all) and can give me an unnatural look > (this may mean that I need to change the 'soften with' setting). > > * the Zone module also doesn't seem to be able to pull down the > brightness of the blown highlights, although it can be used on things > that aren't too bright. > > * Tone curves have defeated my ability to make good fine adjustments at > the bright end of the curve without screwing up the rest of the image. > I assume it's possible but I'm clearly not doing something right. > (I've tried setting the linear preset to freeze most of the 'curve' > and then monkey around only with the top end.) > > (I suspect that this is the right solution and what I want to do is > develop some sort of 'highlight recovery' preset, but it's beyond my > current darktable skill.) > > * the Levels module won't let me move the white point out to the right > (which I think might have roughly the effect I want but I could be > wrong about). > > Since I suspect that this sort of question always works better with an > example, here's a sample D7100 NEF that exhibits the sort of 'blown in > processing' effect that I'm talking about: > > http://www.cs.toronto.edu/~cks/tmp/darktable/DSC_1101.NEF > > (This picture has some genuinely clipped areas, but only a small number; many > more blow out with the default Nikon tone curve.) > > (Note that I'm presenting this for illustrative purposes; I'm less interested > in how to process this specific picture than in how to recover highlights in > the general case that this picture is an example > of.) > > Thanks in advance to anyone who has suggestions, guidance, etc. > > - cks > > ------------------------------------------------------------------------------ > Introducing AppDynamics Lite, a free troubleshooting tool for Java/.NET Get > 100% visibility into your production application - at no cost. > Code-level diagnostics for performance bottlenecks with <2% overhead Download > for free and get started troubleshooting in minutes. > http://p.sf.net/sfu/appdyn_d2d_ap1 > _______________________________________________ > Darktable-users mailing list > Darktable-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/darktable-users > > The content of this email is private and confidential, and unless otherwise > stated only the intended recipient may use the content of this email for its > intended purpose. 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