Trying to figure out cause of nasty aliasing in render
Posted: Fri Apr 21, 2017 4:05 pmSeveral months back, I created proxies for an offline edit with an earlier version of Resolve and an earlier version of CUDA.
The OCNs were UHD XAVC-I from an FS7 and the proxies were UHD ProRes 422 Proxy.
The proxies came out fine, and the offline editor, working in Premiere, would render out 1080p H.264 drafts that looked great. So Premiere was downscaling our UHD proxies to 1080p H.264, without any issues.
Here's a still from a proxy that's looking fine: http://imgur.com/a/lGJH4
Recently, we conformed back to the OCNs inside Resolve and were prepping a "single-clip" 1080p export for a 1080p finish.
The plan was to render the UHD XAVC-I to 1080p ProRes 4444. Unfortunately, Resolve now seems to be reading the OCNS with pretty nasty aliasing, and it does pass that aliasing along into the ProRes 4444 export. Whether merely previewing 1080p out of the DeckLink Mini Monitor or looking at the 1080p ProRes 4444 export, the aliasing is quite bad.
Here are stills of the 1080p DI, before and after some grading:
Log: http://imgur.com/mYeat1G
Some grading: http://imgur.com/a/sg8JS
Notice the edge of the subject's left shoulder. Compare the proxy to the ungraded and graded DI.
Image Scaling was set to "Sharper," and we tried all the settings for "Anti-alias edges:" auto, on, and off. Nothing seemed to improve the aliasing.
My hunch is that this might just be a CUDA issue, because that's the major thing that seems to have changed, but I'm not sure. I'm wondering how I might try to diagnose and fix this.
System specs:
NVIDIA Web Driver 378.05.05.05f01
CUDA driver 8.0.81
DaVinci Resolve 12.5.5.026
MacPro5,1 (Mid 2010)
macOS Sierra 10.12.4 (16E195)
NVIDIA GeForce GTX TITAN X 12288 MB (9-series with MacVidCards firmware)
There is an update for the NVIDIA Web Driver available, 378.05.05.05f02, but I'd like to confirm whether that would fix this issue before I update. Does anyone know of any issues with 378.05.05.05f01 or is there something else I might be missing?
The OCNs were UHD XAVC-I from an FS7 and the proxies were UHD ProRes 422 Proxy.
The proxies came out fine, and the offline editor, working in Premiere, would render out 1080p H.264 drafts that looked great. So Premiere was downscaling our UHD proxies to 1080p H.264, without any issues.
Here's a still from a proxy that's looking fine: http://imgur.com/a/lGJH4
Recently, we conformed back to the OCNs inside Resolve and were prepping a "single-clip" 1080p export for a 1080p finish.
The plan was to render the UHD XAVC-I to 1080p ProRes 4444. Unfortunately, Resolve now seems to be reading the OCNS with pretty nasty aliasing, and it does pass that aliasing along into the ProRes 4444 export. Whether merely previewing 1080p out of the DeckLink Mini Monitor or looking at the 1080p ProRes 4444 export, the aliasing is quite bad.
Here are stills of the 1080p DI, before and after some grading:
Log: http://imgur.com/mYeat1G
Some grading: http://imgur.com/a/sg8JS
Notice the edge of the subject's left shoulder. Compare the proxy to the ungraded and graded DI.
Image Scaling was set to "Sharper," and we tried all the settings for "Anti-alias edges:" auto, on, and off. Nothing seemed to improve the aliasing.
My hunch is that this might just be a CUDA issue, because that's the major thing that seems to have changed, but I'm not sure. I'm wondering how I might try to diagnose and fix this.
System specs:
NVIDIA Web Driver 378.05.05.05f01
CUDA driver 8.0.81
DaVinci Resolve 12.5.5.026
MacPro5,1 (Mid 2010)
macOS Sierra 10.12.4 (16E195)
NVIDIA GeForce GTX TITAN X 12288 MB (9-series with MacVidCards firmware)
There is an update for the NVIDIA Web Driver available, 378.05.05.05f02, but I'd like to confirm whether that would fix this issue before I update. Does anyone know of any issues with 378.05.05.05f01 or is there something else I might be missing?