How to create a P4K LUT by combining two LUTS?

The place for questions about shooting with Blackmagic Cameras.
  • Author
  • Message
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

How to create a P4K LUT by combining two LUTS?

PostSun May 09, 2021 2:22 am

I would like to create a LUT by combing two LUTs for the P4K camera. I have tried different ways of doing this. They all worked as expected within Resolve, but not on camera.

I want to combine the P4K extended video LUT and a black+white LUT. the ones I created worked as expected in resolve. But, it is the same as the black+white alone.


In resolve, I added two nodes: one for extended video LUT, one for B+W LUT, then generate a new LUT.

The base file is a BRAW 8:1 Film

I also tried using Briz LUT converter. The software can actually merge two LUTs directly.

I have also tried the extended video LUT within the camera. Nothing changes.

I have attached the black+white LUT.

Can someone help create one or know how?

Thanks
Attachments
01_Black and White LUTs_Classic B and W.zip
B+W LUT
(330.36 KiB) Downloaded 151 times
Offline

CaptainHook

Blackmagic Design

  • Posts: 2054
  • Joined: Wed Aug 22, 2012 4:50 am
  • Location: Melbourne, Australia
  • Real Name: Hook

Re: How to create a P4K LUT by combining two LUTS?

PostMon May 10, 2021 12:44 am

Assuming you mean Gen 5 Extended Video and assuming you want the extra contrast from the B&W LUT, the attached should do it.
Attachments
Blackmagic Gen 5 Film to Extended Video_B&W.cube.zip
(334.54 KiB) Downloaded 58 times
**Any post by me prior to Aug 2014 was before i started working for Blackmagic**
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

Re: How to create a P4K LUT by combining two LUTS?

PostMon May 10, 2021 12:56 am

CaptainHook wrote:Assuming you mean Gen 5 Extended Video and assuming you want the extra contrast from the B&W LUT, the attached should do it.


Awesome, Captain!

I am currently still using the V6.9.6 on a P4K camera. If it is not cumbersome and time consuming, would you be able to make a Gen 4 extended video version?

Greatly appreciated!!
Shaoyan
Offline

CaptainHook

Blackmagic Design

  • Posts: 2054
  • Joined: Wed Aug 22, 2012 4:50 am
  • Location: Melbourne, Australia
  • Real Name: Hook

Re: How to create a P4K LUT by combining two LUTS?

PostMon May 10, 2021 1:20 am

Attached
Attachments
Blackmagic Pocket 4K Film to Extended Video v4_B&W.cube.zip
(486.42 KiB) Downloaded 59 times
**Any post by me prior to Aug 2014 was before i started working for Blackmagic**
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

Re: How to create a P4K LUT by combining two LUTS?

PostMon May 10, 2021 2:36 am

CaptainHook wrote:Attached


Hey Captain,
Thank you very much for the help. I have just given it a test and here are the feedbacks. Here are the scenarios:

Top Left: BRAW Ext Video + B+W LUT
Top Right: BRAW Ext. Video + Captain's Mod LUT
Bottom Left: BRAW Film + B+W LUT
Bottom right: BRAW Film + Captain's Mod LUT

The combo LUT did not seem to increase peaking intensity despite having more contrast.

It appears that baking two LUTs into one is different from applying two LUTs in sequence. The ext video LUT is more like a converting LUT, the Black and White LUT is grading LUT. I think the order might be important when applying them in camera. This is different from Resolve, I guess.
Attachments
LUTs.jpg
LUT testing
LUTs.jpg (911.91 KiB) Viewed 1739 times
Offline

CaptainHook

Blackmagic Design

  • Posts: 2054
  • Joined: Wed Aug 22, 2012 4:50 am
  • Location: Melbourne, Australia
  • Real Name: Hook

Re: How to create a P4K LUT by combining two LUTS?

PostMon May 10, 2021 3:29 am

3DLUTs for monitoring won't affect peaking unless they are in the record path for baking into ProRes recordings. So unless you do that it's expected they won't affect peaking the same as the record page dynamic range settings.

On the other hand when shooting Blackmagic RAW if you plan to use Video or Extended Video I would always recommend using the record page options over the 3DLUTs for monitoring. You can still change it in post, but the conversions are done with math that will have less interpolation issues than a 3DLUT, and processing 3DLUTs in post on desktop is also going to have worse performance than the Video/Extended Video decode options in the RAW panel too.
**Any post by me prior to Aug 2014 was before i started working for Blackmagic**
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

Re: How to create a P4K LUT by combining two LUTS?

PostTue May 11, 2021 1:10 am

Thanks Captain!

I will give up trying.
I will have to change to ext video in the recording page instead.

Thanks
Offline
User avatar

David Chapman

  • Posts: 461
  • Joined: Thu Nov 08, 2012 11:05 pm
  • Location: Dallas, TX

Re: How to create a P4K LUT by combining two LUTS?

PostTue May 11, 2021 12:44 pm

Hey @CaptainHook!
How did you go about making those LUTs? Was this a process in resolve or did you use a different app?
David Chapman
Just another creative dude with a camera.
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

Re: How to create a P4K LUT by combining two LUTS?

PostTue May 11, 2021 11:25 pm

David Chapman wrote:Hey @CaptainHook!
How did you go about making those LUTs? Was this a process in resolve or did you use a different app?


I read somewhere he uses 3D LUT creator, then adjust them in Resolve and generate from within resolve.

I actually have a question for him. Why I can't load the LUTs created from 3D LU Creator directedly to P4K camera? The camera won't import them like the ones generated from the Resolve.
Offline

CaptainHook

Blackmagic Design

  • Posts: 2054
  • Joined: Wed Aug 22, 2012 4:50 am
  • Location: Melbourne, Australia
  • Real Name: Hook

Re: How to create a P4K LUT by combining two LUTS?

PostWed May 12, 2021 12:09 am

In this case I used Lattice cause it was faster for me to open and combine LUTs, but you can do the same thing in Resolve by applying the LUTs to sequential nodes (in the order they should be processed of course) and generating a new LUT.
**Any post by me prior to Aug 2014 was before i started working for Blackmagic**
Offline

CaptainHook

Blackmagic Design

  • Posts: 2054
  • Joined: Wed Aug 22, 2012 4:50 am
  • Location: Melbourne, Australia
  • Real Name: Hook

Re: How to create a P4K LUT by combining two LUTS?

PostWed May 12, 2021 12:12 am

Shaoyan wrote:I read somewhere he uses 3D LUT creator, then adjust them in Resolve and generate from within resolve.

I actually have a question for him. Why I can't load the LUTs created from 3D LU Creator directedly to P4K camera? The camera won't import them like the ones generated from the Resolve.

I haven't used 3DLUT Creator much since I joined Blackmagic in 2014.
Likely they're not exported in the Resolve specific cube format which is what the cameras support. Not sure if 3DLUT Creator has the correct option (I don't have it on this machine to check) but you could always just do the above and apply the LUT to a node and generate a new one to convert it if you don't have a LUT utility app like Lattice.
**Any post by me prior to Aug 2014 was before i started working for Blackmagic**
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

Re: How to create a P4K LUT by combining two LUTS?

PostWed May 12, 2021 1:11 am

CaptainHook wrote:
Shaoyan wrote:I read somewhere he uses 3D LUT creator, then adjust them in Resolve and generate from within resolve.

I actually have a question for him. Why I can't load the LUTs created from 3D LU Creator directedly to P4K camera? The camera won't import them like the ones generated from the Resolve.

I haven't used 3DLUT Creator much since I joined Blackmagic in 2014.
Likely they're not exported in the Resolve specific cube format which is what the cameras support. Not sure if 3DLUT Creator has the correct option (I don't have it on this machine to check) but you could always just do the above and apply the LUT to a node and generate a new one to convert it if you don't have a LUT utility app like Lattice.



Thanks for responding. They were exported in cube format. It is actually the default format.
Offline

CaptainHook

Blackmagic Design

  • Posts: 2054
  • Joined: Wed Aug 22, 2012 4:50 am
  • Location: Melbourne, Australia
  • Real Name: Hook

Re: How to create a P4K LUT by combining two LUTS?

PostWed May 12, 2021 1:19 am

Cube format doesn't necessarily mean Resolves cube format.
For instance, in Lattice you have the options as shown in the attached for cube format.
They also have to be in the size the camera supports (17^3 or 33^3)

cube variants.png
cube variants.png (74.74 KiB) Viewed 1542 times
**Any post by me prior to Aug 2014 was before i started working for Blackmagic**
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

Re: How to create a P4K LUT by combining two LUTS?

PostWed May 12, 2021 1:44 am

CaptainHook wrote:Cube format doesn't necessarily mean Resolves cube format.
For instance, in Lattice you have the options as shown in the attached for cube format.
They also have to be in the size the camera supports (17^3 or 33^3)

The attachment cube variants.png is no longer available


No it does not have Resolve Variant option, just the extension of cube. the resolve does recognize it, however. but not the camera.

Here is the page regarding file format. I guess it does not support Resolve variant.

Saving LUT-file:
.3dl (Photoshop);
.cube (Iridas, After Effects);
.csp (Cinespace32) – spline interpolation is used;
.png GPUImage;
.png Unity 3D (LUT size 16 and 32);
.png Amplify Color (LUT size 32).
Attachments
3dlut_manual_english.zip
file format
(95.79 KiB) Downloaded 44 times
Offline

CaptainHook

Blackmagic Design

  • Posts: 2054
  • Joined: Wed Aug 22, 2012 4:50 am
  • Location: Melbourne, Australia
  • Real Name: Hook

Re: How to create a P4K LUT by combining two LUTS?

PostWed May 12, 2021 2:10 am

Resolve will open more formats than it writes as.
Whats the LUT size? If the LUT size is 16^3 or 32^3 as described for those other options try converting to 17^3 or 33^3 as mentioned above.
Otherwise most simple way is to use Resolve to convert the LUT or a utility app that you can specify the correct options.

This information is in the manual:
Your Blackmagic Pocket Cinema Camera supports 33 point 3D LUTs in .cube format created in DaVinci Resolve and 17 point 3D LUTs converted to Resolve .cube format via LUT conversion programs. Your camera processes 3D LUTs using high quality tetrahedral interpolation.
**Any post by me prior to Aug 2014 was before i started working for Blackmagic**
Offline

Shaoyan

  • Posts: 73
  • Joined: Sat May 11, 2019 3:00 pm
  • Real Name: Shaoyan Zhang

Re: How to create a P4K LUT by combining two LUTS?

PostThu May 13, 2021 1:02 am

CaptainHook wrote:Resolve will open more formats than it writes as.
Whats the LUT size? If the LUT size is 16^3 or 32^3 as described for those other options try converting to 17^3 or 33^3 as mentioned above.
Otherwise most simple way is to use Resolve to convert the LUT or a utility app that you can specify the correct options.

This information is in the manual:
Your Blackmagic Pocket Cinema Camera supports 33 point 3D LUTs in .cube format created in DaVinci Resolve and 17 point 3D LUTs converted to Resolve .cube format via LUT conversion programs. Your camera processes 3D LUTs using high quality tetrahedral interpolation.


Thanks Captain!!!

That trick worked.
for everyone who is intersted, LUT size 17 is the one the camera will take.

Thanks a million!!
shaoyan

Return to Cinematography

Who is online

Users browsing this forum: Michał Matwij, Sean van Berlo, Tim.Willis and 78 guests