Blackmagic Forum

I'm wondering if any of you can recreate this problem in DR 16.2. I'm seeing a thin green line on the right side of picture when the source is 2048x1152 2K 16x9. The problem goes away when I downgrade to DR 16.1.2. I'm not seeing it on Windows or OpenCL or CUDA GPU processing. Only on Mac with Mojave and AMD with Metal GPU processing. And only on ProRes HQ render. I didn't see it on DNxHR. I see it on both a Mac Pro tower and MacBook Pro. If you have this configuration, try this test:

1. Open a new project with a 2048x1152 2K 16x9 timeline.
2. Throw a solid color effect (white or grey would be easier to see) onto the timeline and turn it into a compound clip, or just load a 2048x1152 ProRes HQ clip if you happen to have one.
3. Render it out to ProRes HQ 2048x1152.
4. Bring it back into Resolve and put in the same timeline.
5. In the viewer, zoom all the way in to the very right edge.

Do you see a thin green line? It shows up on my internal scopes as well in the green channel.

Kelly,

Off quick tests, I cannot see this happen on DaVinci Resolve 16.2.055 Studio /iMac 2015 (Mojave, AMD R9, Metal) - both in the viewer and scopes, the rendered HQ shows an identical scope signature at the grey point to the grey background compount clip.

No line on the borders, no spikes visible.

Could you list more detail on your DaVinci Resolve version and system please?

Thanks
Shrinivas

Shrinivas Ramani wrote:Kelly,
Could you list more detail on your DaVinci Resolve version and system please?

Thanks
Shrinivas

Thanks for testing this out.

My laptop:
Late 2016 15" MacBook Pro.
2.9 Ghz Intel Core i7
Graphics Radeon Pro 460 4GB.
Memory 16 GB
Mojave 10.14.6

I normally don't do any grading on it. Good for testing.

My cMP:
Mac Pro (Early 2009) upgraded to 2012
2x3.46 Ghz 6-Core Intel Xeon
Graphics Radeon Pro VII 16 GB with Pixlas power mod
Memory 64 GB
Mojave 10.14.6

The same green line is visible on both Macs when rendering out 2k 16x9 ProRes HQ from a 2k 16x9 timeline. The green line goes away if I switch the Macs to OpenCL, but then they are much slower. The green line also goes away if I downgrade to DR 16.1.2.

My PC has 2 Nvidia 2080Ti cards and does not exhibit this behavior. The Mac Pro is mainly my ProRes dongle for the PC. Here are screen grabs from the Mac Pro. One with no zoom, and the other with input sizing zoomed in.

The scopes indicate other artefacts on the picture apart from the grey and blanking black - does this happen only on render, or when viewing a grayscale image too?

Could you attach a DRP file so we can get a better idea of the project and render settings?

Thanks
Shrinivas

Shrinivas Ramani wrote:The scopes indicate other artefacts on the picture apart from the grey and blanking black - does this happen only on render, or when viewing a grayscale image too?

Could you attach a DRP file so we can get a better idea of the project and render settings?

Thanks
Shrinivas

DRP Attached. Also attached are the render settings and another screen grab, this time from the MacBook Pro instead of the Mac Pro. The first clip is the compound clip source and the second clip is the rendered file brought back into the timeline. You have to zoom all the way in to see the green line as it might be only 1 pixel wide. There is no green line visible on the first clip (source) while in the timeline.

The green line is visible when brought it and appended to the existing timeline. It's not there when just doing HD resolution. Only 2k 16x9 for some reason. The green line is also visible on the Decklink video out to the video monitor.