500 mirror lens

I bought this lens a couple of years ago. I thought it was good value when I bought it but I could not get it to focus accurately so it went into the equipment bag and gathered dust.

Today I got it out to try again. I still cannot get clean pictures but that seems to be the lens not my eyes. Maybe thats how mirror lens work, or maybe it was cheap because it does not work

This picture is not clearly focused but I liked it so I thought I would share