Although I have since sold my JMI NGF-S focuser and replaced it with an Optec TCF-S, the NGF was a nice focuser that served me well. I just wanted to have a focuser that I could control from a computer -
although the NGF has a visual digital readout, it has no input or output capabilities.
One thing I quickly realized when I had the NGF-S was that every time I turned it on, there was no way of knowing where it was or when it reached the end of it's travel. By adding a microswitch and 12 volt LED
light, I would run it in until the LED turned on and then zero out the digital readout. I would then move it out until the counter read 600, which was the half-way point.
This turned it into a repeatable system from shot to shot or night to night.