Lumetri grade and exported .cube file does not match

[Richard Crook]

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?

[R Neil Haugen]

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

[Richard Crook]

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]

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

[Richard Crook]

Tried changing the extension and imported into a blank Lumetri effect,

here's what I got:

Richard Allen Crook

Filmmaker

[personal info deleted by mod, forum policy]

On Tue, Dec 6, 2016 at 6:50 PM, R Neil Haugen <forums_noreply@adobe.com>

[R Neil Haugen]

As I'm not seeing anything there ... is that something didn't link/load, or ... you got a blank?

Neil

[Richard Crook]

Pics won't post from my phone.  Basically the image is a blue black mess...in other words didn't work.

[R Neil Haugen]

Hmmm ... still puzzling on this one.

Neil

[Richard Crook]

Yeah it is.  Here's a link to the .look file.  See what you think:

CPF_Filmic1.0.look - Google Drive

[R Neil Haugen]

I'll look at this later today.

Neil

[Richard Crook]

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]

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

[Richard Crook]

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]

Huh.

So saving both a Look and a .cube file from within Lumetri, applied later in another Lumetri, they don't work the same?

I just tested this ... the .cube did exactly the same thing in both Basic & Creative tab slots as the corrections saved, the Look of course was only usable in the Creative tab slot. But whether using the .cube in Basic tab or .cube or Look in Creative, the results were identical.

Now ... is this only from viewing within PrPro, or is this viewing the media after exporting it?

Neil

[Richard Crook]

Okay.  Try this.  Import the "Filmic1.0" look file to the creative tab in lumetri on a clip.  Now export a cube file.  Copy the clip to the 2nd track above the original and replace the look file with the cube file.  Now switch between track 1 (the one with the look file applied) and track 2 (the one with the cube applied) to compare the two.  Can you see that the cube file looks differently when it should look the same?

[R Neil Haugen]

I'm not getting anything different doing that.

Take a clip, do something obvious that runs to the edge of the scopes. Save as a Look & a .cube.

Apply a second clip either over or beside the first, same clip.

Apply either one to either clip.

If I just butt one clip after the other, it doesn't make any difference. The scopes show exactly the same thing.

If I stack the clips, then look at just one clip,by turning off the other track, I get the results of ... exactly the same.

If both clips are "on", of course ... I only see the top clip as it is above therefore blocking the image of the lower clip. So unless the upper clip's track control "eye" is set to blocked/off, I can't see anything done to the lower clip.

Neil

[Richard Crook]

Right I am merely talking about comparing the two images.  So when you create a CUBE from my LOOK file and import it into Lumetri (effectively comparing the CUBE and the LOOK), you are saying they look identical?  Hmm.  Post a screenshot of both.  Even Adobe acknowledged the difference.  Again you need to use MY LOOK FILE I posted earlier. 

[R Neil Haugen]

I'll got an errand to run, will come back to the shop and try this in an hour or so with your Look file.

Neil

[R Neil Haugen]

Ok ... downloaded that earlier link, and it's frustrating.

If I use it as a Look, my program monitor just goes black. Zip zero nada.

If I change the extension to .cube, I get a really harsh, dark image.

Neither of which is correct, I'm sure.

So something is screwy with that file as it downloaded to my machine, and clearly not the way it works on yours.

Neil

[Richard Crook]

Well the LUT is designed for Sony s-log3, so unless your source file is close to a log gamma like that, it will look super contrasted and oversaturated.

As for your monitor going black, do you have to restart premiere to fix it?  If yes, then it's the dreaded  compatibility issue of which you can find numerous threads attempting to remedy it.  Usually a wonky driver version or one particular section of an effect that causes the driver to fail. In my case, if I use feathering in ultrakey, the screen goes black because the driver fails and I have to restart premeire.  Either Adobe fixed that in the last update or nvidia fixed the driver in an update...i have no idea

[R Neil Haugen]

I've got some Log footage on a drive not connected right now, so I reverse-engineered a "Log" file. I took a "standard" clip on a sequence, and put your Look on it in Lumetri, plopped an RGB curves on it ahead of Lumetri, and set the curves to give a mostly decent image (black/white points ok, contrast & color not too far off) so I had a "baseline" of what your Look does. Made a .cube file.

Dropped another copy of the clip next to itself, copied the RGB Curves ahead of the Lumetri, applied the .cube made in the last clip to it ... and yes, the result drops about 10 points (of the 100 left-side scale) in the highlights, a tiny amount in the blacks, and also drops blue saturation a noticeable amount.

So yes, your LUT/Look doth not work well "cloned" via Lumetri.

I'm guessing ... that this happens at least in part because of the way Lumetri is designed. I don't agree with it ... but as patiently explained by the engineers at NAB the last two years, the Lumetri panel has both the Basic and Creative tabs designed not to allow the user to "break" their media, the word always used. In other words ... if you've got a clip that has higlights and shadows close to the 100 and 0 points ... you can push that data up to just inside 100 (say 99.5?) and down just to above 0 ... maybe 0.5.

You cannot move data to above or below those numbers. Within the Basic & Creative tabs.

What's worse, if your media has signal data outside the 0.5/99.5 "outer limits" ... nothing you can do in the Basic & Creative tabs can touch that data. Move the Black & White controls ... you can create an amazing gap between what are now blacks and light grays on the bottom and blown-whites and light grays on the top.

The Curves and Color Wheels and HSL tabs can touch that outer data ... but if you do anything to the Basic & Creative tab controls after working the data within bounds in say Curves, you've just gone back to the whites & blacks being outside the limits. And mangled the image of the clip.

So I'm thinking that this might be causing what's happening ... the Lumetri controls are biased against massive changes, and this Log-to-Normal LUT/Look is way past what Lumetri will handle while behaving itself.

Trying to think of what to do next.

Neil

[Richard Crook]

Who knows.  It's pretty lame.  I wanted to create a cube file from this LUT to stick in my FS7 for monitoring but it's useless due to the tonal shifts.  Best I can do is try to create a new LUT without importing other LUTs. 

[R Neil Haugen]

Yea, frustrating. I think this LUT is "extreme" enough in how far it pushes the signal that Lumetri doesn't handle it well. I just wish Lumetri was built with the expectation that it was going to be used by grownups.

Neil

[chrisw44157881]

I had a transform LUT not work as expected until I nested the video first. i perceive it as a bug even if its what adobe intends.

[Richard Crook]

I believe it to be a bug as well.  Can you clarify your steps of nesting the footage?