M42 to Canon Eos Lens adapter

I bought a lens adapter for some of my old film lenses recently for 8 bucks I thought it was worth a shot. I like it so far but there are a couple of drawbacks. It is a bit difficult to get in focus with my 28mm prime but my 50mm is easier. The other drawback is you kinda have to guess your exposure as it doesn't read the F-stop from the lens. My Canon XSI Thinks the Fstop is zero and if you try to get the exposure correct in manual mode it is usually over or underexposed. For the price it doesn't really bother me. These photos are jpegs straight out of my camera with no adjustments what so ever.