Topic: PSA to artists: how to upload images uncompressed to Bluesky

Making posts via Bluesky’s official interface will first transcode/compress your image to their preset JPEG within your browser, then upload that compressed file to the server.

To avoid this extra compression and instead have your file uploaded verbatim, one should call the com.atproto.repo.uploadBlob XRPC directly; there are third-party interfaces which wraps this in a nice and familiar UX flow.

I’ve personally found that https://atproto.at has the best usability for this use case of making uncompressed Bluesky posts.

Interesting...shame you need these extra steps to not let BS themselves just wreck a bit all the art lol.

Does PostyBirb utilize this endpoint? I know a lot of people use that to upload art.

After a cursory glance at PostyBirb’s repository I do not find any code for clientside compression, which would make sense as the compression is an extra step you’d need to go out of your way to implement.

A quick test you can use to confirm is by uploading a PNG from it and check with atproto.at or pdsls.dev to see if it remained the identical file.