I picked up a Bintel 0.5 FR a little while ago..... Not giving great results with the ED80. Is this all I can expect from this FR? - or have I done something wrong. I'm sure the lens isn't perfectly square in its holder???
Focus not perfect in this shot - on axis focus was achievable, just lots of aberrations as shown as you head off-axis.
I just had the FR screwed into the nose piece of the DSI - I couldn't get any image with the extension tube that was supplied with the FR....
It's always something!