How to output high quality 360 VR video with Premiere Pro? When editing a 360 video in Adobe Premiere Pro, I noticed that if I import the video into the program and export it again without any additional changes, the resulting file size of the output file is 10 times smaller than the original, and the output file is lower resolution and appears blurry compared to the original. The file has been captured with a Garmin VIRB 360, video duration is 4 minutes, the original file size is 3 GB, and the output file size is 300 MB. I run a Windows 10 machine.

Here are the properties of my sequence: 4736 x 2496, 00:03:56:01, 29.97 fps, 48000 Hz - Stereo, VR Projection: Equirectangular, VR Layout: Monoscopic, VR Captured View: 360° Horizontal by 180° Vertical. I exported the file using the following settings: Format: H.264, Preset: Custom, and ticked the box saying "Use maximum render quality"

How do I export 360 video out of Premiere and still preserve the original 4K quality of the footage?

EDIT:

I found a youtube tutorial for how to preserve video quality on a Mac here, but I'm using Windows, and instead tried the export settings listed here. The settings were: "H.264 format with the Match Source preset. Disable the match source check boxes for dimensions, profile, and level. Change the profile to High and the level to 5.2. Choose Stretch To Fill in the Source Scaling setting (**couldn't find this one, so didn't do it**). Disable the aspect ratio link next to the dimensions and change the dimensions to 4096 by 2304 (or 2160 for 60 fps). Select a high bit rate, such as 100 Mbps. Enable Use Maximum Render Quality to achieve the best scaling results."

Unfortunately, the difference in quality is still substantial.
Here is a frame zoomed in at maximum level for the original file: 
And here is approximately the same frame zoomed in at maximum level for the exported file:
Format: h.264 -> that's what makes it look bad.

h.264 is a codec in the mp4 container and always compresses, making the file smaller and look worse. For lossless exporting you use prores 4444 xq if you're using mac (or windows with the newest version of premiere) or DNxHR. I highly recommend prores 4444 xq though.