You asked
Is the ttartisan 100mm f 2 8 2x macro hard to focus manually?
The TTArtisan 100mm f/2.8 2X Macro is manual focus only, with no autofocus, so you'll turn the focus ring yourself for every shot. My pages don't say how it feels to focus by hand, so I can't tell you whether it's hard or easy to use.
At 2X magnification, depth of field is very shallow up close, so precise focus matters. A magnified live view or focus peaking on your camera will help a lot, so check those before you buy. You can see which bodies it fits on its catalogue page.
If you're shooting on APS-C, the lens frames tighter than its 100mm marking, as explained in the Focal length converter.
Written by Claude from this site's pages.