Celestron C8 EdgeHD focus jam with ZWO EAF - seeking expert advice

Tony Gondola · Jan 11, 2026, 07:17 PM

You stated that the manual focuser won’t move in any direction, is that with the EAF detached because if that’s the case, the problem is on the SCT side, not the EAF side. Does the EAF function when not coupled to the SCT focuser?

At this time, I have not disassembled the EAF from the focus mechanism. I will attempt it tomorrow to see if the problem is in EAF or the SCT side.

I do see that the EAF does attempt to twist both side visibly, but stops within half a second - as if it has hit some hard limit.

PS: I just edited my post to say "The EAF does not move in any direction” to avoid any confusion.

My experience with my EAF was such as to make me swear off ZWO ASI equipment.

Finding my EAF had NO repeat accuracy I sought ZWO services help. Sent it in with detailed descriptions. They returned it with a “No Problem Found”.

I immediately tested it on my desk, and the same problem was still there, it could function out but would arbitrarily stop when sent inward. The stop required a reinitiation manually to get it to move inward again. It could not focus.

They ask if I could make a short video of what it was doing. So I did. But…. they have no means of accepting the file. 🤨 So I posted it on my You Tube channel and sent a link. Once I had taught them how to troubleshoot the problem and sent them the defective EAF for the second time they finally relented and replaced it. Why does a customer have to go to such great lengths to prove a piece of their product is defective?

They did not reimburse me for the EAF hand controller ($40) I was forced to buy to show the defect. It was a long denial on their part that my EAF was defective.

The replacement now lives on my old 80mm Triplet the Grandkids have set up at the Son’s home and they love it. The electronic focuser lets them adjust the focus without touching the telescope.

I replaced my EAF focuser with a Pegasus Astro Focus Cube2 which I chose for its separate 12-volt motor power input. Not loading up my USB network. It has worked flawlessly and is amazingly precise in focusing my 130mm Rack & Pinion telescope.

So, I have lost all faith it ZWO ASI products. Love my 3 ASI cameras but will be looking elsewhere as they fail. Getting away from the China business model. They can KMA!

Sorry to hear you are going through the throes of ZWO. My relief has been Pegasus Astro. Focuser, Rotator, and Flatmaster 150.

akshay87kumar · Jan 15, 2026, 05:27 PM

SonnyE · Jan 15, 2026, 04:11 PM

My experience with my EAF was such as to make me swear off ZWO ASI equipment.

Thanks for sharing your experience. I have been a long time user of ZWO equipment - partly due to very limited availability of astrophotography vendors at my location.

This experience with a brand new EAF used only for 1 night is very irksome. I did have a growing list of equipment - ASIAIR, 2 EAFs, 2 EFWs so far. I have moved to NINA, and slowly growing comfortable with it, so I may evaluate the options definitely.

Ahh, NINA!

NINA, the best avenue I can suggest is Cuiv the Lazy Geeks visual tutorials for NINA. While he is a bit of a goofy geek I found a great deal of substance in his video steps. I decided to knuckle down and get NINA working for me.

I find I really like using videos because I can pause, back-up, refer, and check if something comes up. A great learning tool.

A couple of years ago now I started getting serious after ~9.5 years with my first “real” telescope, an Orion ED80T CF, a triplet refractor with a carbon fiber tube. It worked very well for me during that time, wore out several cameras, taught me a great deal. Even destroyed my first mount, which was a POS. It lives at the last Grandkids’ Dad’s house where they and friends use it for fun visual use.

I eventually went to upgrading my endeavors with my Astrophotography. In doing so I quickly realized NINA does have a list of equipment it works best with. I let that help guide me as I explored my options. I found I wanted things that were open sourced as far as their software is concerned, or at the very least, ASCOM compliant.

ZWO ASI writes or steals software to make their equipment work. Once one begins down their equipment path it practically demands you continue to invest in their brand. Not just me saying that, but many others in our astronomy community. I listened and wondered. I have 3 of their cameras which I have enjoyed using. As long as you download the specific software (not unique to ZWO, others also have software packages specific to their products.)

But for me, to engage NINA fully and become enabled to do full remote operation (which in my case amounts to ~75 feet, as the crow flies.) And get away from one corporate entity, I paid attention to NINA’s drop-down lists as far as brands were concerned.

My bad experience with ZWO service in New Jersey cost them my consideration to get an ASI Air and watching them inadeptly float their rotator offering affirmed my decision to steer clear of them. I was enjoying my Pegasus rotator for about a year while they kept ping-ponging ASI fans over their version of a rotator.

Hope you can find useful help in Cuiv’s stuff.