. I think I'm just going to get a $10 reversing ring on Amazon for right now and see how things go.
Be aware that you need the ability to stop a lens down when using a reversing ring, so that limits you to older lenses with manual aperture rings plus a method to stop them down. I find that a M42 lens with a eos adapter on it can be used with a reverse ring. The EOS adapter holds the aperture pin in, so that the aperture will stop down.
This was taken with a Sigma 105 and a helios 44-4 which is a M42 mount. I hacked it so that I can always adjust the iris. Should I stop down the Helios instead of the sigma when shooting?