I'm using Rush to work with 4k 30fps files captured by my S10. Bitrate of these files is about 46/50 Mbps.
During the edit everything is ok Problems began during the rendering and export phase: obviously I would like to export in 4k (2160p) at 30fps with the SAME QUALITY of the input files so I select these options (Photo 1):
Estimated File Size: 287 MB (31 sec of video)
Result File Size: 41 MB
I supposed that High for quality maintain the same bitrate of input files so the quality could be considered high, but I was wrong…
After the rendering, Rush returned a file with a bitrate of 10 Mbps that is ridiculous for 2160p videos
And the problem is that is impossible to change the bitrate! Playing the video you could see lots of compression artifacts and the video isn’t good for anything!
So I tried to use other preset and see what happen with the same project: 1) With the same configuration but setting Resolution at 1080p the output file size is 73 MB and the quality is quite good (it’s a high quality FullHD video with a bit rate of 18/20 Mbps)
2) Using the Youtube 4k 2160p UltraHd preset is possible to see the interesting thing (Photo 2): the Quality setting is now on Custom (40Mbps) and after the render Rush give me a file with a size of 149 MB and a bitrate of 40 Mbps.
The quality of this video is very high and (now) I’m going to use that file.
But it’s a ridiculous thing that if I select high quality, I get a file with a horrible quality and artifacts.
So now… Is possible to change manually the bitrate and get enough quality? Because now I can't use 2160p@60fps videos from my S10 with a bit rate of 75 Mbps. Or at least correct this bug about video quality.
I’m really sad about that because I really love Rush: perfect for cut some scenes and create easy Video in few minutes instead of Adobe Premiere Pro that take me lots of time for little adjustments …
Thanks for every answer! (and sorry for my English ahaha)