NEF (Nikon Raw) to linear EXR

astar wrote on 7/27/2015, 1:49 PM

Does anyone know of a way to convert Nikon raw to linear EXR, for work in Vegas?

I have been using Raw Therapee to convert to 16bit Tiff, then importing that into Vegas. This process works well, but I cannot believe this would be the same results as going straight to 16/32bit FP space of EXR.

Comments

balazer wrote on 7/27/2015, 3:51 PM

Vegas doesn't read 16-bit integer still image formats correctly. It applies some weird curve.

You can use dcraw or Raw Therapee to convert your Nikon raw images to linear 16-bit TIFF. But you'll need some software to convert from TIFF to EXR. I haven't found any yet.

What are you trying to accomplish? Are you working with stills, or video frames?

astar wrote on 7/27/2015, 7:01 PM

Trying to do some 4k time-lapse but convert the raw data directly to linear EXR. From what you said , and my research on the matter this is not available yet.

Could not get dcraw to work, and the conversion scripts I did find looked to convert to an intermediate before going to EXR. Trying to avoid the curve you refer to, and maintain the 14-bit color info. The RawTherapee process works, but you have to set some levels like a 4.0 gamma to get it up to where you can start tweaking levels individually.

balazer wrote on 7/27/2015, 10:23 PM

Since Vegas can't read 16-bit integer formats correctly, unless you can find some software to convert to EXR, your next best bet would be to convert from 16-bit TIFF to 10-bit V210 AVI with ffmpeg. You don't want linear encoding, in that case. Set RawTherapee to generate output in a normal display-referred color space like sRGB or Rec.709 with gamma around 2.2. Basically all of the level and color tweaks and display rendering should happen in Raw Therapee, and Vegas would just be doing the video editing part.

I think dcraw should work, but it has no particular advantage over RawTherapee, if you can get RawTherapee to do what you want.

astar wrote on 7/28/2015, 5:31 PM

I was trying a workflow of NEF to ACES, the 16-bit conversion seems to working fine with out conversion to EXR. Ultimately I would like to get to EXR but at the moment mostly for academic reasons.

Here is what I have so far:

Seems like the NEF -> Rawtherapee -> 16-bit tiff linear ->Vegas in ACES RTT SRGB - > render as XAVC ACES RTT SRGB works well. It is interesting to see how the RTT transforms the waveform in the final render. The original levels are between 0 and 100% in 32bitFL, but the RTT brings things down to peak about 80-85%.

I did attempt the RTT-709 but the black levels seems a bit high. I do not have a 709 TV to try it out on however. My monitor is set to SRGB.

balazer wrote on 7/29/2015, 1:14 PM

Here is my workflow for getting raw images into ACES.

I think you can ignore the differences between sRGB and Rec.709. Just use the Rec.709 ODT, and add contrast as necessary. The Rec.709 ODT often doesn't have enough contrast.

What input color space did you use? Your results look oversaturated, making me think you used the default or ACES color space as your input, which wouldn't be correct.

jwcarney wrote on 7/30/2015, 5:22 PM

You could use imagemagick to convert from raw to jpeg2000 or EXR
http://www.imagemagick.org/script/index.php