4K 60fps - How can I reduce Youtube compression artifacts?

[travise38589766]

I've been recording 4K 60fps videos on my GoPro.  It's mostly walks and jogs on trails, nothing really wild in terms of movement. 

I edit the videos in Premiere Pro, and then export them using VBR 2-pass with a target bitrate of 75 and max of 100.  I then upload the exported video to YouTube, wait for HD Processing to finish, and view them in my browser on various computers and my 4K TV.

I'm noticing lots of compression artifacts (patches of blurriness) on YouTube, usually on distant trail surfaces, but also sometimes in the underbrush or on distant mountains.  When I am jogging, I get more artifacts than when I am walking.  Standing still is best.  So the faster I move, the more artifacts I get.

How can I decrease the compression artifacts?

Are there settings in the GoPro that can help? I'm using the GoPro's high bit rate setting, and have experimented with different levels of sharpness and other settings, but don't have a feel for which settings work best.

When exporting with Premiere Pro, is a target/max bitrate of 75/100 good for 4K 60fps, or should I go higher?  It's already taking multiple days for YouTube to finish the HD processing for my videos, so I haven't tested other bit rates.  Are there other settings in Premiere Pro I should try?

Thanks a bunch!

[travise38589766]

OK, that makes sense.  Are there advantages to going higher than the source bit rate (120)?  The only effects I'm usually applying are fades.

[R Neil Haugen]

It's mainly that you don't probably want to go lower ... and so depending on the data rates of the various options, one that you might want might be a few Mbps higher than the original.

Typically you'd go with the one next lower, but ... again, it depends on your testing.

Neii

[travise38589766]

OK, I re-processed a bunch of recent videos at CBR 120. 

I recorded some more tests a couple days ago.  This time all on bike, which I've never recorded with GoPro before.  Because I was moving faster (and without a gimbal), the footage isn't as clear as I'd get walking, but it's not too horrible.  Here's a short excerpt:

https://www.youtube.com/watch?v=TKnezoCPTWU

To be honest, the most distracting thing about this video is the GoPro's attempts to smooth out the motion when I am looking left or right; it ends up looking weird.  That's something I'll have to work out on through practice... *if* I end up shooting more bike videos like this.

Thanks for your help.  I'm getting to the point where I think I need to focus on technique and planning... and learn some of the fundamentals.  I wish I could take a course on this stuff.  It's a pretty specific use case, though.