These are great. I had a Stiletto focuser tuned for the Pentax K1000. You can actually make your own knife edge focuser that work quite well. In the age of computer controlled digital motor focusing through FHWM calculations and others, such a tool is no longer required. I got easily frustrated changing the focuser with the camera and back again. As the night air cooled introducing subtle changes in focus, I did swapped regularly. Drove me insane. Now with temperature compensating computer controlled focusers, this is a thing of the past.
