A Step-by-Step Guide to ZWO EAF Backlash Calibration and Tuning

If you have a ZWO EAF (Electronic Automatic Focuser) this video will show you to use the ASIAir App to calculate and calibrate for the backlash of your telescope.

Note only the ZWO EAF is compatible with the ZWO ASIAir ecosystem, but the same theory shown in this video can be applied to other brand focusers using other apps and software.

*Non sponsored affiliate Links for stuff in this video – costs you no extra but supports this channel if you make a purchase. I appreciate you :)*

*Agena Astro*

*Highpoint Scientific*

[betafoofoo]

This is a great example of how these videos should be made. Excellent tutorial, no waffle, silly music or graphics. Just straight to the point with clear informative instruction. Thanks Glenn you have been really helpful.

[marvinwhisman]

Really well done. Great job of both explaining backlash but also showing how to adjust for it.

[subodhshetty]

Excellent and easy to follow. Thanks much 🙏🏼

[clancym]

What a terrific " this is how to do it" video. New subscriber. Much thanks for taking your time to make this video. Really great. Mike

[mikerogers]

The backlash you are demonstrating there looks huge. I started experiencing some serious backlash on my ZWO EAF and i tracked it down to slop in the main gear/shaft inside the EAF. Taking it apart and re-assembling is easy ( voids any warranty of course, but this is not a particularly expensive part). I applied a tiny drop of CA glue on the shaft before reinstalling the main gear to get a tight fit. Backlash is almost zero !

[AntonioPena]

Very simple and effective presented, many others tried to explained, but you nailed perfectly in few minutes, thanks for sharing your method.

[stevenmartell]

Thanks so much for this, Glenn. I was wondering how I was going to go about fixing the backlash issue, so thanks for making this video and having it just make sense.

[cford]

This was an awesome and very easy video to understand. Now I'm gonna go calibrate both my scopes EAF.

[whatmattersmost]

Great video and the best way of setting backlash I have seen! It's VERY important when using Nina or AsiAir Auto Focus!

[gregmac]

Perfect!

Excellent tutorial and simply explained with a clear presentation... Bravo!

[thatastrochap]

Very nice explanation and demo. Definitely going to check my backlash setting and update it. Thank you!

[BlueTurtleStudios]

That was great Glenn. So well explained I could follow easily. Good Job!

[ShayneMostyn]

I looked for this gearing on my phone and couldnt find it ;) Seriously though mate, I think this is one of your best put together videos, well done

[mikelockwood]

excellent video - it's the simple things that make a huge difference

[MartinLeeney]

Great concise video. Thanks for taking the time to explain it so well.

[darkrangersinc]

One option you may want to look at for the future for not much more is the Primaluce Sesto Senso it essentially eliminated the backlash in my autofocus routine. Obviously that’s only going to be usable for Nina but if you ever do go that route, I don’t have to do any backlash compensation and my focus curve looks really good and immediately starts changing from the very first step

[TheRhike]

Incredible useful and concise video, many thanks!!

[raymahl]

Thank you so much for this explanation!

[coolabahwoodworking]

Great video man. That is really interesting. I didn’t know that happens at all 😮

[TheTabugman]

Thanks for the video! Another YouTube channel (can't remember which one) said that the Asiair calculated the EAF backlash automatically...? 🤔