Color Problem emerged on a totally fine project suddenly

[davedelizza]

I export a version recently, wasn't really looking at color because that had already been done and settled on, I haven't touched the color in months. No LUTs were used in this project, it was all manual and the client was REALLLY particular about it. The last version, they called out that it was looking different. I open it. Surely it is. The project was started in 2022. A weird collection of bugs, namely around the text window prompted me to open it up in 23, which has been really stable for me. I would like to blame that, but that's actually not the case. I opened up the old project from 22 as well, and for whatever reason, the actual source clips are just darker. I open them in VLC, don't look that way. Attached is a screenshot of the Program from PP next to Resolve. There are NO source clip effects, I checked. The color settings themselves have not changed. I don't know what this is, some sort of weird gamma bump or something? Nothing else on my computer has changed, that I can think of. Really praying for an easy dumb fix that i'm missing here. I've not touched any of the color settings since I deduced that the source clip interpretation or whatever has changed.
Project colorspace is 709. I turned on and off Composite in Linear Color and Display management, no real effect there.
Footage: FS7
Operating System: Windows 10 Home 64-bit (10.0, Build 19044) (19041.vb_release.191206-1406)
Processor: Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz (12 CPUs), ~3.7GHz
GTX1080ti 8gb Driver 526.98

[Kevin-Monahan]

Hi Dave,

Can you check clip Properties? Were the clips shot in HLG/HDR? SLOG? Let us know.

Thanks,

Kevin

[davedelizza]

File Path: D:\Camera_A\Roll_1\Roll_1\Clip\A001C001_220624V8.MXF
Type: MXF
File Size: 324.18 MB
Image Size: 1920 x 1080
Frame Rate: 23.976
Source Audio Format: 48000 Hz - 24-bit - 8 Channels
Project Audio Format: 48000 Hz - 32 bit floating point - 8 Channels
Total Duration: 00:00:27:00
Pixel Aspect Ratio: 1.0
Alpha: None
Color Space: Rec. 709
Color Space Override: Off
Input LUT: None

MXF File details:
Wrapper type: MXF OP1a (type: SingleItem SinglePackage MultiTrack Stream Internal)
File generated by: Sony, Mem (2.00)
AVCI 100
Bitstream Format: Sony
Gamma: S-Log3 Cine

[R Neil Haugen]

The default base changed in 2022 from 2021, and has again in 2023.

Sony Slog3 now is 'recognized' by Premiere and it applies a transform of some kind to it, though it will 'see' this as an HLG clip, so to use on an SDR/Rec,709 timeline, you need to set the Override-To option to Rec.709 ... that internally sets the NCLC tag meta for Premiere as to how to interpret the file data.

You can either use how Premiere rolls that into Rec.709 by simply giving that Override-To setting, or you can drop your own wide-gamut to Rec.709 conversion LUT in the Input LUT slot of the Interpret Footage CM section. You would still need to flag that internally as Rec.709 with the Override-To option.

Neil

[davedelizza]

Thanks for this info Neil. When I did the "override to 709" on the clips, it didn't actually change anything on the clip in the source. What is the difference between the override modes of 709 and 709 (Scene)? 

I ended up just tweaking this color to match the old correct one again as to not have to wonder if any of this nonsense will change again.

[R Neil Haugen]

They are working on adding more options to color management, bringing Premier from a Rec.709-only app to a more modern color space agnostic app. And so ... the changes, which are necessary but are rather a pain to adjust to at times.

They had to make changes. We ain't Rec.709 only anymore.

Rec.709 applies full Rec.709 including the Bt.1886 display gamma of 2.4, as called for since that was added to Rec.709 back when CRT monitors were discontinued. Those monitors had a natural physical equivalent of the 2.4 gamma curve.

Rec.709 scene does not apply the display gamma, and is the same as the camera applies originally to the file. Gamma 1.96.

In the 23.1 update released a day or two back, they've also added tonemapping as a choice. So many logs, including particularly the Sony logs, can be set to a Rec.709 timeline via tonemapping. Another change.

The Override-To option in the Modify/Interpret Footage dialog essentially tells Premiere what NCLC tags for color space/range you want it to 'see' and apply to the file. It's called an 'Override' because whatever you tell it to do, it will do no matter the tag (or lack thereof) of the video file itself.

Premiere will then apply the appropriate math on that sequence for the file.

And yea, this inclusion of tonemapping is another change that you can opt for that will affect the look of the file. Most S-log-3 I've used the tonemapping on in the Public Beta ... it seemed to work pretty good.

You can also apply a manufacturer's LUT conversion/normlization LUT in the Input LUT slot of the Interpret Footage dialog, then use the Override set to Rec.709, and make sure Tonemapping is not selected in the Preferences, and get what you may have gotten before.

Neil

[davedelizza]

Very informative neil, thank you very much for this. I feel like I can't
get ahead with color knowledge.

--
David DeLizza

[R Neil Haugen]

It's pretty frustrating at times, yea. But once you start working with it, and know what to do with the at times oddly named options ... it starts working.

Neil