That’s a lot of images …
-(source_url:http* AND source needed),-derpibooru exclusive
results in 2,560,689 hits … I’m not even sure I’m searching for that right.
source_url and NOT
derpibooru exclusive AND NOT
source needed …
-derpibooru exclusive,(source_url:http* AND NOT source needed)
? Nope nope nope, that finds stuff like >>2902256
But, within those, the first thing I noticed is that a lot of them are screencaps or stuff where the artist listed their patreon in the description or something like that.
So … the source isn’t so much ‘needed’ as it is not in the source_url.
(source needed AND description:http*),-(source_url:http*) might be useful, to find images where there’s a source in the description but not in the source_url, but the first thing I found were images where the http:* was a link to some meta image or something … soooo … oof.
I mean, it sounds like a great hobby if you’d like to work those, and worth doing. But, man … that might be a lifetime’s work.
Only 392,859 in that set, which is actually survivable.
That even finds images like >>2902337
, where the artist is known and actually a user of this site so maybe we could ask them if they should be providing a source, or if they are uploading exclusive images.