Skip to main content
Richard Crook
Richard Crook
Known Participant
December 6, 2016
Question

Lumetri grade and exported .cube file does not match

  • December 6, 2016
  • 3 replies
  • 6378 views

Maybe I'm missing something.  Does the Lumetri export option to CUBE leave out some information?

Here's the problem.  I created a grade that I use all the time with the Lumetri grading effect, and I want to export a .cube file that I can import into my camera for on-set monitoring.  The problem is, when I export the .cube...the grade doesn't match.

Here's the grade:

Here's the .cube file I created from that grade...imported as a creative LUT into Lumetri with no other settings adjusted:

Am I missing something here?

    This topic has been closed for replies.

    3 replies

    R Neil Haugen
    R Neil Haugen
    Legend
    January 11, 2020

    Axel....

     

    Not all color/tonal corrections can be transferred to a LUT ... LUTs are said by colorists to be the dumbest math out there. All a LUT does is have a chart ... pixels with X/Y values become S/Q values ... and so on. That's it. So not everything can be reduced to a LUT. It's why there's so much trouble with LUTs clipping or crushing things. HSL secondary corrections at times will not properly be "applied" via LUT to another clip, for instance.

     

    Which is why saving something as a Lumetri preset "works" when the other's haven't. Saving it as a preset means the entire effect will be set as you last used it. Saving as Cube and as Look are similar to each other but not exactly the same. Yea, at times they can get different results.

     

    Neil

    Everyone's mileage always varies ...
    Richard Crook
    Richard CrookAuthor
    Known Participant
    February 23, 2017

    Talking to support, they have found that because I started with a third-party LUT applied and exported the cube from there, the cube will not look right.  So they blame the third party LUT and nothing else.  Doesn't make any sense to me...but whatever. 

    R Neil Haugen
    R Neil Haugen
    Legend
    February 23, 2017

    You started with a 3rd party LUT applied ... I hadn't seen that mentioned.

    So how about giving a complete step by step of what you're doing? Might have an educated thought then ...

    Neil

    Everyone's mileage always varies ...
      Richard Crook
      Richard CrookAuthor
      Known Participant
      February 23, 2017

      Add lumetri to an uncolored clip.

      Add 3rd party LUT.

      Make adjustments.

      Save a look file and a cube file.

      Apply lumetri to another uncolored clip.

      Import the look file that was just created = perfect color.

      Alternatively, import the cube file that was just created and replace the look file to the same clip = incorrect color

        R Neil Haugen
        R Neil Haugen
        Legend
        December 6, 2016

        If that exported cube is being applied to the footage above in an un-corrected state, the cube should match.

        I can start with a "clean" non-corrected file, do some work, export as cube, then clear all Lumetri on the clip via the Effects Control panel reset-arrow icon on the Lumetri top line.

        Then I can go back to the clip, applying the cube, and it goes back to exactly where it was before.

        So ... I'm thinking there's a good chance either something that had been done via a different color-effect to the clip you made the cube from, or ... you don't have that clip back to a totally 'clean' state. This process only creates a LUT/Look from the work done in Lumetri, it doesn't "see" the stuff done via other effects.

        So ... check the Master clip tab in the Lumetri panel, all other options, to see if something else is going on there.

        Neil

        Everyone's mileage always varies ...
        Richard Crook
        Richard CrookAuthor
        Known Participant
        December 7, 2016

        Yes that's my summation on how it would work. No, nothing else has been done to the clip. Again, when I export the .look file and import it, it looks exactly the same. Only the cube isn't working.

        R Neil Haugen
        R Neil Haugen
        Legend
        December 7, 2016

        Huh, the CUBE works just fine here ... now, a Look file is an Adobe created CUBE file, if I recall correctly. Can you rename the Look file by changing the extension, and get it to work? I can export a Look file to the Technical folder, close PrPro, navigate to the file in Explorer & change the extension, re-open PrPro, and it 'shows' in the Basic Tab's dropdown list and applies exactly as before to the clip.

        Does that work on your end, and ... can that file then work in-camera?

        Neil

        Everyone's mileage always varies ...
        Terms & ConditionsAccessibility statement
        Using the community Terms of use Privacy Cookie preferences Do not sell or share my personal information ad choicesAdChoices