Could Someone help me? When I render and image, it in 8k quality with the best anti-alliasing, and it looks OK. But when i upload it to instagram it gets even worse, it doesnt look great, when for example all photos on greyscalesgorilla's instagram page are really good quality. What sould I do? Thanks for the help!
I would check with Instagram and find out what native display resolution they're using. If you give them something much larger than they will display, they will obviously have to downsample and recompress the image. At that point they are in control of how the final image will appear.