Strange occasional grain/overlay effect after rendering

[romainj35502393]

Hi!

Since I've been using my new computer, there's been a weird grain/overlay effect on my videos after rendering. You can find one example of that at the 1.00 mark here: https://www.youtube.com/watch?v=-iL2frYN96Y .

Any idea where that could be coming from?

Thanks in advance!

[R Neil Haugen]

What's the capture device? What's the format/codec, and do you have any effects applied, color, anything? Any chance it's VFR ... variable frame-rate, as from a phone or tablet? Any sizing, speed changes, anything?

Neil

[romainj35502393]

Hi! Thank you for replying.

I'm using a Panasonic Lumix G7 for filming. Format is H.264, and I'm using the YouTube 4K preset for export. Both the device and settings are what I have been using for quite some time now, and I may be wrong but I believe this problem first appeared when I started using my new computer, which should be more powerful than the previous one. No effects whatsoever, just standard editing with volume changes and crossfades. 

[R Neil Haugen]

Again, what settings/effects, also the GPU?

Neil

[romainj35502393]

Hi,

Sorry for not being clear, this is all quite new for me and I don't know much about Premiere or editing in general yet. Not sure what you mean by settings/effects, but if those are the sequence settings, Timebase is 25 frames/second, Frame size is 4K, pixel aspect ratio is Square Pixels (1.0) and Working Color Space is Rec.709. As for the project settings, my renderer is Mercury Playback Engine GPU Acceleration (OpenCL), there's no Preview Cache, and capture format is DV.

As I said I don't think I've been using any effects, just fades. 

My GPU is a Radeon RX 550 (I'm adding a spec sheet below just in case).

Again, thank you so much for helping me out and sorry if I missed anything or forgot to mention anything important!

Romain

[R Neil Haugen · Accepted solution]

Have you tried going to the Project settings dialog, and setting "Mercury Acceleration" to software only? This cuts out your GPU use in Premiere, but will tell us if it's a GPU problem or not.

Neil

[romainj35502393]

I just tried that and there's no glitching whatsoever in the video, so I guess that was the issue! A big thank you for your help, Neil, that's much appreciated! 🙂 

[R Neil Haugen]

Check for a new driver for that card then. Or if it's on the latest, roll back a driver.

Neil