When I post something I've made on Facebook, it always gets ruined. Seemingly, whether I post a clean PNG, a high quality JPG or a reduced-quality JPG of my vector art, Facebook's automatic conversion seems to constantly turn everything into an awfully dirtied up JPG. For instance, see this, my page for my school's graduates' album:
Original on the left, what Facebook did on the right:
(If you're curious, the bubble says "I'm first and foremost a simple girl.")
Look at how dirty some of the red areas got. And compared to some other works I posted in the past, this is a mild case of ruined-ness.
I thought about hosting the image on another site, and it works, but is there something I can do with my image beforehand to avoid it being ruined by Facebook, so that I could simply use Facebook's built-in upload feature and not worry about it?
For instance, a certain specific kind of setting or compression level that it would detect and not re-compress it. Or a certain image format that would somehow be less affected by Facebook's compression.
Best Answer
Facebook is not for original-quality image-hosting, but it's great for promotion.
I would advise you to store the originals on a hosting site that does not modify the originals, post a smaller version to facebook (optimised according to other links in comments), and link to your original. Possibly, linking to the original will provide a good-enough-quality thumbnail to avoid posting an image to Facebook at all, saving you a step.
To automate the process, you might be able to hook an IFTTT script up to your image-host and Facebook to auto-post your new images.