Confused about using dcraw external to lightzone


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berbmit
Confused about using dcraw external to lightzone

So I'm trying to understand why my images are varying when using dcraw external to lightzone, compared to lightzone's own conversion of the raw (RAF) file.  I'm working in Linux Mint 17.1

I converted a Fujifilm RAF (taken in sRGB color space) file with dcraw v9.19 (computers system default) and with v9.26 to 16 bit TIFFs, staying with sRGB, using camera white balance and the embedded color matrix (dcraw -o 1 -w -v -6 -T +M)

Then I used lightzone (4.1.1) to convert these TIFF files and also the original RAF file to jpeg.

The dcraw v9.19 and 9.26 differ in the color result (possibly not suprisingly as dcraw's treatment of RAF files has supposedly changed).  The dcraw v9.26 conversion's color is very similar to lightzone's conversion, but the lightzone conversion gives an over-exposed solution.  In lightzone I can of course under-expose the image to get a similar result to dcraw's vanilla conversion.

I'm wondering why lightzone's default conversion is over-exposed compared to lightzone's?  I find the external conversion by dcraw to be a far better starting point for post-processing.

Here are the images

Lightzone's conversion of the RAF:

dcraw v9.26

And for interest, dcraw v9.19 (Linux system default)

 

tex
Yes, it's interesting...

And it's a good example of how LZ just uses dcRaw as a starting point.  All I can say is that I've seen this sort of thing before, and it has to do with the raw tone curve we (or you...) generate using studio test samples from Imaging Resource.  If you look at the DIY raw profiling instructions and video, you'll see how a very human element comes into play.  I have seen some really peculiar raw tone curves.  And I have seen at least one (the old Oly E-510, I think) that tended to blow highlights.  This may be the case here, and I recommend , if you are interested, unlocking the raw tone curve in LZ for this, take a snapshot of it, save that somewhere, and then try creating your own raw tone curve and compare the 2.

What program did you use that included dcRaw versions to compare to LZ?

Photonoxx
As Tex said, It's probably

As Tex said, It's probably due to the default raw tone curve for your camera in lightzone (which model do you use ?). Probably, you can, as Tex says, unlock the Raw tone curve and tweak the hilghlights part of the RTC and when satisfied save as a style.

 

Personally, I have a Fuji X-E2 and I use differents RTC depending of the photos I work on. One of my RTC is used to recover more highlights. 

Bulent Celasun
I have a similar problem

I have posted a similar problem. I just wanted to add here that my converted files look similar to yours, only uglier!

I also have a problem with unwanted cropping of the rotated RAW images. That cannot be due the improper raw curve.

I have tried to unlock the default curve. It, sort of works. Still, for a consistent workflow, I would much prefer a nicely made curve. Perhaps I should try making one again watching Doug's video once more. (In my earlier message, I said Tex's. Sorry for my poor memory). 

tex
Bulent---

Please see my reply to your other post.

Photonoxx
For the cropping matter, it's

For the cropping matter, it's a usual Lightzone dysfunction that add a crop section in style files.

You can fix this by creating a style for which you select only the Raw Tone Curve tool, and after that, you edit this style and replace :

<crop>........

....</crop>

 

by

 

<Crop Angle="0.0"/>

 

I hope this fix could be integrated in future LZ release