hallo,

is there good way to prevent double uploads.

i normally just type in the name of the artist and some tags to see if its already here but that does not always work.

is there some better way?

The e621 reverse image search http://iqdb.harry.lu/

For example you want to upload http://www.furaffinity.net/view/15044908/. You enter the image url into the reverse image search. You find out there's already a better version (post #1271971).