10-bit proxies look like 8-bit in Lumetri Scopes

[robertd19572356]

Re-rendering some 10-bit 422 camera files to Cineform for easier playback on timeline. When I comapre the files in Lumetri scopes, the re-rendered proxies have that 8-bit look compared to the original (steps in the waveform, noise in the vectorscope, etc). Screengrab attached.

Shouldn't  both sets of scopes look the same? Nice and smooth?

To my eye, both files look almost identical in the program window, so maybe I shouldn't care?

[chrisw44157881]

that is bad. does it appear if you enable max bit depth in sequence setting?

have playback and paused playback to high quality and resolution 100%?

what happens if you try prores with max bit depth in sequence and export/reimport?

[R Neil Haugen]

Um ... first, the original file is both heavily clipped at whites, crushed blacks, and severely exceeds saturation limitations. So there's some issues there to start with. I don't know if that's color space or dynamic range mismatches or what. So it would be nice to know what color space they are.

Second, these are proxies, and one doesn't use proxies for tight evaluation, simply for a facsimile image that plays back easier (especially with effects). If you need full quality for an evaluation, you turn off the proxies. So ... I wouldn't see a problem anyway. Still, nice to check on this.I'd love to get a sample clip of this and try it on my machine.

Further question ... do you have Max Bit Depth set in the Proxy preset?

Neil

[robertd19572356]

UPDATE: I was able to make the scopes look more like the original by clicking " RGBA 12-bpc + alpha" instead of "YUV 10-bpc" under "Render at Maximum Depth."  I uploaded a smallish (300MB) original camera file if anyone wants to play themselves:  https://drive.google.com/drive/folders/1lhpiU46YF3jyjqmP-LCeCEgYSdTyuW-w?usp=sharing

Before, I tried everything I could in the export settings in media encoder, including max depth.

The levels are crazy because I applied an extreme garde in lumteri to highlight the problem. But the steps and noise in the scopes are still there with no grade applied.

People often rerender camera files to a better format and get rid of the camera files. There should be a way to make a lossless copy in a more edit-friendly codec.

[R Neil Haugen]

I use typically MediaEncoder with carefully crafted settings for t-codes. Or (in the past) HandBrake and now ShutterEncoder for t-codes of H.264/5 VFR to CFR, as I can bump the settings there to get high-Q t-codes, definitely would be "visually lossless" through a couple generations.

But it can take practice.

Proxies, typically, one doesn't worry about the high-q data, they're just a playback tool. For evaluations, click back to originals.

T-codes ... yea, you want those high Q.

Neil