Low cost 500mm mirror on K5
I went to a motorcycle event and grabbed some shots. SR really works even at this focal length. The last image was shot at 1/60 and still is quite sharp. The mirror is a Samyang F6.3 that can be purchased new for about $115. It's hard to focus but works well when you get it right. Focus confirmation works but it seems to take a while to respond. I had tried one of the F8 mirrors from same company but it was not very good. It think this lens works well for the money.