You asked
What are the alternatives to the ttartisan 7 5mm f 2 fisheye?
The only other lens I have listed as a close match is the 7Artisans 7.5mm f/2.8 Fisheye II. It's also a 7.5mm prime for APS-C cameras, so it covers the same kind of ultra-wide fisheye work.
The main difference is aperture. At f/2.8 it lets in about one stop less light than the TTArtisan 7.5mm f/2 Fisheye, so it's a bit harder in dim rooms. It also gives slightly deeper depth of field at the same framing, which can help when you want more of the scene sharp.
I don't have the full mount list or specs for the 7Artisans lens here, so check its page to confirm it fits your camera before you buy. If you need a faster fisheye than f/2.8, the TTArtisan is the one to get.
Written by Claude from this site's pages.