Stellarvue 102 with reducer and optec focuser fails

I have tried everything I can think of . step size when talk to optec they say 50-75. forum group says 100-200. Here are host of issues.

  1. curve will complete to 100 percent look good and than when rerun wont work
  2. will go thru the process and wont end will just keep rerunning the autofucus.

equipment is as follows:

Stellarvue 102 with .80 reducer so focal ratio is 5.6
optec **DirectSync SV 3.0 focuser
atik 460ex mono 4.54 u
zwo filter wheel

Thank you



Do you still have the logfile for the night in question? If so can you post it? It’s hard to point to a problem without any data to look at.

Did you notice at all what quality level your AF runs achieved? It should be in the log file or an AF pack if you saved these. My first thought is that despite ‘looking good’ the quality score achieved was below the required target level, thus triggering a re-run.

With regard to step-size, did you take a look at the number of focuser steps needed to go from smallest HFR to c 3x this value (x1.5 if looking at HFD), see AF set-up notes.

Here is the log. I have tried what you suggested and still had problems. I will try again

how do I load the log to here?

Under SGP Help Menu there is an option to Report a Problem, This has an option to load a log file

I had a similar problem with my SV115. It turned out that I had not tightened my Crayford focuser in a few years and it was slipping with the heavy camera (QSI-683). After tightening my focuser, the AF worked fine. Of course, if you have the rack and pinion focuser, this is not likely to help.


so here is the strange thing. I went thru the calculation and got a step size of 173, 2x2 binnng. I worked perfect after I did that (ran it 15 times). I did not adjust the backlash as stayed at 40. The next night with great skies I went to same location 19,740 ran auto and no V curve and could not get auto focus to work. when I went back to same location, stars were out of focus at same location. I am using an optec directlyncs focser . Beyound fustration. Totally frustrrated. Any help would be greatly appreciated.