Panasonic v-log, 3d conversion luts, and linear 10-bit

Help/How To
1

Hello, everyone. I’m obviously brand new here, hopefully my inexperience doesn’t cause my questions to be too much of a headache. :slight_smile:

Short version: Is it even possible to use a v-log to rec709 conversion lut (or any other kind of conversion lut) when using Shotcut in “Linear 10-bit” processing mode? I’m guessing “No,” but I’m trying to understand the details.

I am very new to video editing and to Shotcut. I have experience processing raw still photography with different tools like darktable and RawTherapee, but I feel very much at sea when it comes to things like video color spaces and conversions.

I have 3d luts created with the spektrafilm-lut tool in Spektrafilm by Andrea Volpato for converting Panasonic v-log files to rec 709 (and applying the appropriate look). I’m assuming there is some kind of two-step color space conversion when Shotcut is set to “Linear 10-bit” and that these luts are never going to work if they are in the wrong spot in the pipeline. Is there a way of getting them in the correct spot, or is this never going to happen? Or, do I need a different kind of conversion lut?

Spektrafilm-lut has a wide range of options for input and output spaces:

lists

Input choices:

ACEScc                       acescc
ACEScct                      acescct
ARRI LogC3 (EI800)           logc3
ARRI LogC4                   logc4
Adobe RGB                    adobergb
Apple Log                    applelog
Blackmagic Film Gen 5        bmfilmgen5
Canon Log 3                  canonlog3
DCI-P3                       dcip3
DJI D-Log                    dlog
DaVinci Intermediate         davinciintermediate
Display P3                   displayp3
Fujifilm F-Log               flog
Fujifilm F-Log2              flog2
Nikon N-Log                  nlog
P3-D65 PQ                    p3d65pq
Panasonic V-Log              vlog
ProPhoto RGB                 prophoto
RED Log3G10                  redlog3g10
Rec.2020                     rec2020
Rec.2100 HLG                 rec2100hlg
Rec.2100 PQ                  rec2100pq
Rec.709                      rec709
Sony S-Log3                  slog3
Sony S-Log3 (S-Gamut3.Cine)  slog3cine
sRGB                         srgb

Output choices:

Adobe RGB     adobergb
DCI-P3        dcip3
Display P3    displayp3
P3-D65 PQ     p3d65pq
ProPhoto RGB  prophoto
Rec.2020      rec2020
Rec.2100 HLG  rec2100hlg
Rec.2100 PQ   rec2100pq
Rec.709       rec709
sRGB          srgb

I don’t think any of these work in linear space, either.

I wonder if my lay-person’s experience with darktable is working against me. I’m used to doing most of my photo edits within linear rec 2020 and tone mapping, then converting that into the output space as the final two steps. I probably don’t even understand that process well enough to meaningfully understand it outside of darktable.

2

Yes, use the LUT option in Properties that was added a couple of versions ago:

It applies before the conversion to linear.

3

Success, thank you. :slight_smile:

Completely missed that one, I don’t think it’s in the user guide yet?

My version was not as current as I thought it was, and I had to use the portable tar download to find the option, but all is well.