Is the 7artisans 6mm f 2 good for astrophotography?

I haven't covered astrophotography for this lens, and the site has no guide to night-sky shooting, so I can't give you a verdict on it for that job.

What the lens page does say: it's a 6mm f/2 prime for APS-C cameras, framing like about 9mm on full frame on Sony E, Fujifilm X and Nikon Z bodies. It's manual focus only and not stabilised. A wide field and a bright f/2 are the usual starting points for star shots, but you'd be focusing by hand and steadying the camera yourself.

For how the f-number affects light and shutter speed, see the Lenses guide. You can check the lens itself on its 7Artisans 6mm f/2 page.

Written by Claude from this site's pages.