ZWO Electronic Automatic Focuser (EAF)
ZWO Electronic Automatic Focuser (EAF)ZWO Electronic Automatic Focuser (EAF)ZWO Electronic Automatic Focuser (EAF)
ZWO Electronic Automatic Focuser (EAF)ZWO Electronic Automatic Focuser (EAF)ZWO Electronic Automatic Focuser (EAF)

ZWO Electronic Automatic Focuser (EAF)

  (19 Reviews)
✓ 2 year warranty


Out of stock due 7-10 working days

About this product

Model:  zwo_eaf
Part Number:  ZWO-5V-EAF

Latest version - uses 5v USB for Power Supply

ASCOM compliant auto-focuser for your telescope.

Introducing the 5V EAF, this electronic focuser, like its previous version, enables precise, dynamic focus control for planetary and deep-sky imaging, while only connected with 5V USB.

Compatible with the ASIAIR.

A wide range of adaptors are under development - currently supported focusers include:

  • SkyWatcher Astrophotography Reflectors, SkyWatcher Black Diamond, SkyWatcher Dobsonians, SkyWatcher Maksutov-Newtonians.
  • Feather Touch
  • SkyRover, SharpStar, TS Optics and Astro Tech

With an optional adapter the following Takahashi and Vixen telescope focusers are supported:

  • Takahashi FSQ85
  • Takahashi FSQ106
  • Takahashi TOA-130NFB
  • Takahashi TOA-150B
  • Vixen VC200L


  • Size: 60mm x 50mm x 40mm
  • Step motor, 35mm diameter, 5760 steps to rotate a circle
  • Data port: USB2
  • Weight: 277g
  • Capacity: 5kg


Mechanical Diagram

Whats in the box..

Customer reviews

Average Rating (19 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
Thursday, 4 March 2021  | 

Feels and looks like a well build product & smartly finished case. It wasn't designed to fit my particular telescope WO Zenithstar 80 ED but with a few adjustments to the standard bracket supplied I have it very securely mounted. Easy to set up with my software, SharpCap 3.2. Very impressed with the smooth operation and repeatability of focus position. There's more to learn about it's use yet but it's already a winner as far as I'm concerned. Tempted to buy another for my larger scope that is permanently mounted in my observatory.

Rating (max 5):  
Easy to install on the Redcat 51
Monday, 18 January 2021  | 

A couple of cheese plates, a belt drive from a 3D printer, belt, and sprocket (cut to length and glue/sew into a loop £6.50 from Amazon), and it all worked fine.

Rating (max 5):  
Tuesday, 5 January 2021  | 

Took a long time to get due to Covid but a great product.
Works perfectly on an Esprit 120.

Rating (max 5):  
Focus from your warm room
Tuesday, 22 December 2020  | 

This needed some work to fit as I was fitting it to a SW80 with a Moonlite focus rail.
the bracket that it comes with needed a bit of grinding down but it's on and secure, so all happy.
Once again, solid ZWO construction. drivers off the Zwo website and works fine with NINA.

Rating (max 5):  
Great addition to my ASIAir Pro.
Friday, 11 December 2020  | 

Used on my older Explore Scientific 102mm apo it took only a couple of minutes to fit once Iíd found some bolts as the supplied were no use. The build quality is impressive. Iíve used it on several imaging sessions now and it has performed very well. Iím using the ASIAir pro and Iím getting great V curves during the focus routine and low HFD readings. The ability to set autofocus to run every 30 minutes or on filter change or after a set temperature change means I can set it going and just let things get on. No more standing in the cold with a bahtinov mask tweaking the manual focus knob! So far, so good. Letís hope it proves durable long term. As usual, service from FLO was super. I recommend you try this unit. It will make things much easier whether you use SGP, APT, N.I.N.A. Or the ASIAir.

Rating (max 5):  
Thursday, 5 November 2020  | 

These two units integrate seamlessly. I have not had to configure anything to get a working system that focuses better than I can achieve manually. Great to be able to refocus the OTA from the warmth of my study!
For a critical review on backlash etc. please look elsewhere. As it works out of the box with mu Esprit 100ED I am happy.

Rating (max 5):  
Tuesday, 13 October 2020  | 

I bought this as my 1st venture into auto focusing. It looks to be a solid, well made device. I had to get creative when fitting the bracket to my focuser. The bracket has ridges on one side, this was the side that had to face up to my focuser and it was pulling off square when I tightened it down, it would be better if the bracket didnt have these ridges and was smooth on both sides. I'd have given 5 stars were it not for this. Other than this, fitting wasnt difficult and set up was easy.

Rating (max 5):  
ZWO electronic focusser
Tuesday, 29 September 2020  | 

Well made piece of kit. Works well. Just make sure that you can rem ove the coarse focussing knob on your telescope before you buy, (for a horrible minute I thought mine would not). Good value compared to other offerings.

Rating (max 5):  
Great EAF at a good price
Wednesday, 5 August 2020  | 

I am so happy with this EAF that I bought 2. One for each telescope. The only issue I had, was that I needed to find screws that match my telescopes focusers. The screws supplied with the EAF did not fit the SkyWatcher 72ED or the Bresser Messier AR-127L. But I found some in the local store and everything works great.

Rating (max 5):  
Just fitted and "yippee"
Monday, 27 July 2020  | 

Well finally committed to purchasing this ZWO EAF focuser and installed on my TS65 Quad, all fitted without any hole adjustments just one M3 longer screw to lock the bracket to the scope R&P focuser. Connected it all up and with the hand controller connected, loaded the Ascom driver and USB lead and all worked perfectly. Set the zero point limit a small distance away from the maximum "in" position of the drawtube and set the maximum "out" steps to cover my usual focus position and additional couple of 1000 steps and all behaved as expected, just needed to tick box in settings for reversed movement. Tried it out on NINA and APT on the only clearish night so far and both NINA and APT auto focus routines behaved beautifully achieving better focus than I have ever achieved manually with Bahtinov etc. Calculated the overall backlash of EAF and R&P focuser and only 35 steps so set that into both programs and it performs really really well.

Highly recommend and as usual, FLO supply was, as always, brilliant

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