Hi,
I come here after I read on pentaxforum-com about the feature in Rawtherapee 5.7, and like OP ted_smith was thinking great I will process my scans mostly there. And I found like ted_smith that this Negative film tool was missing in the options of the raw panel, then google brought me here.
Ok, so iẗ́’s a tool only for DSLR scans not scanners.
Like ted_smith I have been thinking of Negative Lab Pro. I am a unix/linux user since ever, but if something is really very good or existing only in win I just run that inside Virtualbox.
So I have been playing with Negativelab, which is a Lightroom plugin.
Until now, I have been processing my negatives (Epson V700 for 120 and Proscan 10T for 35mm) in Gimp, and the “Invert” filter, followed by a “Auto white balance” and/or “Normalize/Equalize/Auto levels”. Works well with sometimes just a bit more color/curves/levels tweaks.
I do scan the colour negative in Vuescan, in raw/tiiff as dng, and Gimp does “un-rawize” the file by calling Darktable or Rawtherapee, whichever is in the system, for further editing.
Ok, what I was thinking is: if Gimp does a good job at negative inversion, why couldn’t Rawtherapee do the same for tiff “raw” files from scanners? Of course I wonder because I have no clue about the specs and programmatic technicities.
But then, that’s what the Negativelabpro Lightroom plugin does.
I played with few 6x6 colour negatives.
for instance this is a two steps process in Gimp (invert+auto WB):
and this is two steps in LR+Negativelabpro (LR auto WB + default NLP plugin):
if I add the colour equalization in Gimp, after invert and auto WB (1st image) I get:
the negative used:
So in short it could be nice to have a Rawtherapee module similar to the Lightroom NLP plugin. Yet without it Gimp works.