I’m using N.I.N.A./Skywatcher Esprit 120 ED/Pegasus Focus Cube and a ASI533 mm camera.
I’ve used this setup for a long time with good success. Last night when trying to focus I’m running to 0 and the focus program shows an error.
If I disconnect the Focuser Cube and manually move the focuser to a mid-point, the camera will be extremely out of focus.
How can I correct this problem?
Hank
Disconnect the focus cube coupling, reset it to the middle of it’s range, reconnect the coupling. Do not change the position of the focuser.
Tony, I’m changing the focus cube not the focuser, correct?
Andrea, no encoders.
Hank
Tony, I’m changing the focus cube not the focuser, correct?
Andrea, no encoders.
Hank
That’s right. It doesn’t have encoders but it does use a stepper. It’s pretty much the same as the ZWO unit from what I can see.
andrea tasselli · Sep 12, 2025 at 04:37 PM
Tony, I’m changing the focus cube not the focuser, correct?
Andrea, no encoders.
Hank
*So how does it know at what position it is? I mean physically. If it is anything like mine it is because the focuser is slipping or the joint isn't secured anymore so the shaft is rotating freely. So disconnect the said focuser (while the thing is in focus) from the coupling, run it to mid range and reconnect. Done.
Done. I disconnected the shaft and changed its position from 0 to 1500. Skies might be clear tonight so I can check it out.
Mossyback · Sep 12, 2025, 02:42 PM
I’m using N.I.N.A./Skywatcher Esprit 120 ED/Pegasus Focus Cube and a ASI533 mm camera.
I’ve used this setup for a long time with good success. Last night when trying to focus I’m running to 0 and the focus program shows an error.
If I disconnect the Focuser Cube and manually move the focuser to a mid-point, the camera will be extremely out of focus.
How can I correct this problem?
Hank
I’ve experienced similar problems, Hank. My correction is to open my main camera in ASI Studio (ASI 2600 MC Pro) and operate my Pegasus Astro Focus Cube2 to a place of near good focus. From there NINA can find focus with its FWHM solving.
In my experience that was all it took because if the focusing is too far out, NINA defaults to zero. No need to loosen the coupling.
By changing the coupling centering, it brings in worse problems if you have set your focusing correctly to begin with. 0 is with your focusing tube at 0 Zero, all the way to stop. Then when focused your focuser tube will be somewhere near mid point.
Loosening the coupler negates that initial setting. And Zero is somewhere in La-La land.
If you go back to your initial setup instructions, you can see what I am referring to.