How do I avoid video image quality losses when uploading to Instagram a compressed 45 second video shot in 1080p on a Nikon 5200 DSLR?

How do I avoid video image quality losses when uploading to Instagram a compressed 45 second video shot in 1080p on a Nikon 5200 DSLR? - 1

You don't.

ALL social media sites compress or reduce the resolution of still and video image files to save on storage space and bandwidth.

If you want to post Full HD videos, you can set up a YouTube account and post them there

You can't. All social media sharing sites degrade video quality when you upload. That's to ensure video streaming is quick enough to maintain sanity over the internet. The best way to go about it is to make sure you upload only high quality videos so that even if they muddle it up, your video will still look at least decent. Shooting high quality videos mean you have to know what you're doing with the camera. If you don't get it yet, you should know the basic principles of photography to get the shots right.

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