Review on 📷 Fotasy Canon FD to Sony FE Mount Adapter: Compatible with Sony a7 Series, a9, and a6xxx Cameras by Richard Cartner

You can't really spoil the M42 adapter and this one is no exception. Quite well done, no obvious problems. As an adapter it is excellent and I will have no problem buying it again. There is no light leak that I could identify. I didn't notice any reflections or other issues, although it would have been nice if the inside was lined with felt like I've seen on some other (non-M42) adapters. The only issue I have is how the metal insert is held onto the lens thread. There are three small set screws you can use to adjust it if your lenses are slightly misaligned (e.g. your depth of field chart is always top centered on your lens). They have loosened up a bit despite minimal use (probably loosened at the factory) and for a few minutes I got really dizzy as my lens spun like something out of an exorcist. When I finally removed the lens, it dawned on me why. I also noticed a few small metal shavings that seem to have either popped out from under the M42 insert itself or formed when I had to fiddle with the lens a bit. I highly recommend loosening the set screws and using a blower to remove any debris from under the ring before retightening. Check the set screws regularly to make sure nothing has become loose over time. Nevertheless, I am quite satisfied with both Fotasy M42 adapters. I also have a Nikon G adapter from them and have had no problems with it. Will buy from Fotasy again in the future.