Smooth transitions (dark sky) becomes pixelated

[Sprinterdriver]

Hi.

I've got some recordings (full HD) where the the after dawn sky is in the background. After converting the video file to MP4 (RF = 22-25, x264 preset = placebo, filters = none) I've noticed that the background (dark blue fades into pitch black) turning from a nice looking smooth transition to a ugly pixelating transition with feew colors by big blocks.

I guess that if setting RF to a very low number, I'll get a resulting video that show the fading background in a more eye catching way. I also guess that this is one of few downsides about the x264 compression.

My question is therefore: Is there some setting that give a fair tradeoff between maintaining the nice fading background, and still have a output file that is much smaller than the input file?


Thanks in advance

[Smithcraft]

I've found that the grain tune can help somewhat with the banding.

Also, using the extra settings from this post helped out with at least one source so far:
viewtopic.php?p=129259#p129259

SC

[Sprinterdriver]

Thanks - I'll try that