It may be truth (we need a developer to confirm), but in this case it seems to be working like I say. Try it: - open a picture - over-expose it with the Exposure module - try to recover using the shift white point slider on Shadows and highlights. Doing that, I lose all detail in the highlights. At some points in the pipeline there are color space transformations, and that may clamp the values to the limits to avoid problems (total speculation) Regards, Guillermo
On Sun, Apr 8, 2018 at 8:17 PM, Robert Bieber <[email protected]> wrote: > Don't quote me on this, but since the pixel values are all floats I'm > pretty sure it's possible for one module to push them beyond the "maximum" > values and another one to bring them back in with the detail still there, > as long as everything ends up within the allowable bounds by the time it > gets converted to int > > On 04/08/2018 07:11 PM, Guillermo Rozas wrote: > > Can you provide the original DNG so people can play with it? > > One think you should take into account is that modules in Darktable are > applied in a certain order (bottom to top on darkroom). In particular, > "Exposure" and "Base Curve" come before "Shadows and highlights". So, if > Exposure pushes the info of the sky past the white point, you can not get > it back later (at least that's how I understand it). Going by the > histogram, it looks like this is what happening to your picture (there are > a lot of pixels close to the right edge): the info was there before the > exposure (and base curve) modules, but not by time you get to the shadows > and highlights module. > > Two tips I can give you: > - check the RAW over-exposure indicator (small colors icon below and to > the right of the picture in darkroom). If the area is really > non-recoverable it will show as over exposed in RAW. If not, there is a way > to recover it (not always easy, but the info is there) > - my first step when editing complex pictures is to use the exposure and > black sliders on the Exposure module to fit the data exactly inside the > histogram (using the normal under/over exposure indicator). Then I know I'm > working with almost all the info the file have. > > Best regards, > Guillermo > > On Sun, Apr 8, 2018 at 7:04 PM, Peter Cripps <[email protected]> > wrote: > >> I've seen similar results to Chris. One of the (few) things that I've >> found Lightroom does better than darktable is highlight recovery. >> >> I have noticed that the darktable histogram doesn't seem to show content >> at the far right hand side that does show in the Lightroom histogram. Don't >> know if this is relevant. >> >> I hesitate to mention this, since I'm very conscious of the fact that >> darktable is entirely created by people working on their own time. It seems >> ungrateful to pick out one thing that isn't perhaps as good as with other >> paid programs. >> >> Peter >> >> >> >> >> On 04/08/2018 02:51 PM, Chris wrote: >> >> Hi, >> >> So the shadows & highlights module also does not seem to full 'reveal' >> the detail in the clouds that I know exists... it simply darkens the >> existing pixels that we can already see. So not really 'recovering detail' >> as such. >> >> https://www.dropbox.com/s/u3lo4oy9dokdbwh/darkt_04.jpg?dl=0 >> >> and pushed further >> >> https://www.dropbox.com/s/zih4f434frcxizu/darkt_05.jpg?dl=0 >> >> obviously I am going to extremes here... but they still just do not >> compare to the clarity revealed from LR. >> >> https://www.dropbox.com/s/suw9v3jnsszbsec/lr_02.jpg?dl=0 >> >> Thanks, >> >> Chris >> >> On 2018/04/08 02:30 PM, Pascal Obry wrote: >> >> Le dimanche 08 avril 2018 à 14:25 -0700, Chris a écrit : >> >> Anyway, these are my adventures into highlights in DarkTable. >> >> You haven't activate the "shadows & highlight" module, so indeed >> nothing done for darktable :) >> >> >> >> >> ____________________________________________________________________________ >> darktable user mailing list to unsubscribe send a mail to >> [email protected] >> >> >> >> ____________________________________________________________________________ >> darktable user mailing list to unsubscribe send a mail to >> [email protected] >> > > > ____________________________________________________________________________ > darktable user mailing list to unsubscribe send a mail to > [email protected] > > > > ____________________________________________________________________________ > darktable user mailing list to unsubscribe send a mail to > [email protected] > ____________________________________________________________________________ darktable user mailing list to unsubscribe send a mail to [email protected]
