Blackmagic Forum

Hey everybody,
I'm having a consistent and strange result when attempting to Generate a LUT from analyzed pattern. I've followed the instructions in the manual to a T, but every time I Generate a LUT from pattern it creates a LUT that turns any clip into a solid green swatch of color at 100% saturation.. At first I thought perhaps I was creating a broken LUT based on some non basic correction, but when I attempt the process using only one simple grade, like a hue shift, it will still create a LUT that simply turns any clip into a solid green swatch.

I thought perhaps the analyze command's process of referencing the original trim_lut.dpx was where the hangup was occuring. So I looked closely at my folder structure, and indeed the trim_lut.dpx had been renamed to trim_lut0.dpx. I changed the name back to trim_lut.dpx, but to no avail. I'm still generating the same solid-green-swatch-creating LUT every time. Any thoughts?

Which hardware (CPU, GPU, RAM, disk I/O speed)? What specific version of Resolve? What OS? What source material?

How specifically are you creating a LUT? The way I've generally done it is by right-clicking from a Gallery still, and it has generally worked perfectly. I always bring the exported LUT back into Resolve and double-checked it against the correction itself to make sure it matches.

Marc Wielage wrote:Which hardware (CPU, GPU, RAM, disk I/O speed)? What specific version of Resolve? What OS? What source material?

How specifically are you creating a LUT? The way I've generally done it is by right-clicking from a Gallery still, and it has generally worked perfectly. I always bring the exported LUT back into Resolve and double-checked it against the correction itself to make sure it matches.

I understand the normal process of generating LUTs from Gallery stills, but this does not work when I'm creating a new LUT that has an older LUT as one of the grades. It's LUT-ception if you will.

I'm importing the "trim_lut.dpx" and placing it in a 1920x1080 timeline. I'm making grades onto this trim LUT, and then grabbing a still of it. Then I right click on the still and export that as a new .dpx file, let's call it LUTception.dpx ... then I import LUTception.dpx back into resolve, and place it into the timeline. On the color page I make sure the playhead is somewhere on LUTception.dpx and go into Project Settings -> Color Management -> and click "Generate LUT from analyzed pattern."

this produces a new LUT that has a pure green thumbnail, and turns all clips into a solid green swatch. I've attached a screenshot of what I'm seeing. Thanks in advance for any insights.

EDIT: I was wrong on my premise that you can't create a LUT that incorporates grades using LUTS, I don't know why I initial thought this was impossible but I double checked this morning and it seems to be working. I still don't know why the "Generate LUT from analyzed pattern" function isn't working, but for the time being I don't need it.

I can't replicate your issue. generating a LUT using the analysed pattern works exactly as expected when following the User Manual instructions. I think you may have slipped up in the process somewhere. This function is mainly designed to grab adjustments from a different application by exporting a modified trim_lut.dpx file from a 3rd party application, which Resolve can read and re-create a LUT from.

If you want to upload your modified trim_lut.dpx which contains your adjustments, I can take a look at it for you.

I can replicate this issue exactly when trying to use 'Generate LUT' function from Project settings > Color Management UI:



Is there a solution please?

DR 16.2.7
OSX Mojave
iMac (Retina 4K)
Radeon Pro 560X 4 GB

Did anyone actually manage to work this out? Resolve 17 has now removed this function (maybe because it's so unreliable??), but I've tried to use this tool in versions of both 15 and 16 and I'm just getting a black image.
Kind-of frustrating as this tool potentially allows for some interesting possibilities (being able to, on paper, replicate adjustments into a LUT from applications outside Resolve)