ZWO Electronic Automatic Focuser (EAF) 5V
ZWO Electronic Automatic Focuser (EAF) 5VZWO Electronic Automatic Focuser (EAF) 5VZWO Electronic Automatic Focuser (EAF) 5V
ZWO Electronic Automatic Focuser (EAF) 5VZWO Electronic Automatic Focuser (EAF) 5VZWO Electronic Automatic Focuser (EAF) 5V

ZWO Electronic Automatic Focuser (EAF) 5V

  (46 Reviews)
✓ 2 year warranty


Out of stock due 30-40 working days

About this product

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

This latest version uses 5v USB for Power Supply.

You can now directly connect the EAF to your camera, laptop or ASIAIR PRO via the USB 2.0 port & cable for both data transmission and power supply. This makes cable management easier and reduces power requirements.​ 

Compatible with the ASIAIR smiley

Support list:

  • SkyWatcher Astrophotography Reflectors, SkyWatcher Black Diamond, SkyWatcher Dobsonians, SkyWatcher Maksutov-Newtonians.
  • SharpStar telescopes,
  • SkyRover telescopes,
  • TS Optics,
  • Astro Tech,
  • FeatherTouch

Please note not all models from the brands above are supported.  

For information regarding the full supported list and connection methods, please see HERE:

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

  • Takahashi FSQ85
  • Takahashi FSQ106 (not first generation)
  • Takahashi TOA-130NFB
  • Takahashi TOA-150B
  • Vixen VC200L


  • Size: 60mm x 50mm x 40mm
  • Step motor, 35mm diameter, 7.5° step angle
  • Reduction ratio: 120
  • Data port: USB2, Type-B
  • Weight: 277g
  • Capacity: 5kg


Customer reviews

Average Rating (46 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
Very happy husband
07 January 2023  | 

My husband is very happy with his latest acquisition. As usual the service from First Light Optics was outstanding and this time it didn't even come with clouds or snow and he was able to try it out straight away. We now don't shop anywhere else for his astrophotography equipment. And he just loves receiving their gift vouchers so that he can keep adding to his kit without feeling guilty. I'm afraid I can't give a technical review of the focuser save to say that my husband is happy with it, so it does what it says on the tin!

Rating (max 5):  
ZWO EAF auto focuser
04 January 2023  | 

A well made and easy to fit auto focuser. I fitted it onto my 102 Starfield without any issues. It's operation is smooth and precise and does the job perfectly. It's also great that it includes the different fittings for various focusers. Well worth buying. Fantastic service from FLO again as is the norm.

Rating (max 5):  
30 December 2022  | 

Brilliant service and speedy as always

Thank you

Rating (max 5):  
Easy Life
15 December 2022  | 

Wish I had got this ages ago.
Really simple to use and works great with the ASI AIR
Plug and play really and speeds up setup time.

Rating (max 5):  
Fitting the ZWO EAF to a SkyWatcher 190MN
25 November 2022  | 

Firstly, this is an excellent quality piece of kit, the actual fitting of which itself was quite straightforward. There is a caveat to that. You may be faced with the need to change which side your dual focuser is on as the EAF can only be attached in place of the course adjustment knob. On the 190MN, I needed remove four allen screws from the base and undo a further grub screw holding the dual speed side, then slide the spindle assembly out for refitting from the other side. Once in position, the last grub screw referenced will need to be removed and inserted in the side twith the dual speed knobs, and the four allen screws securing the whole assembly. That's the messy bit over with and so on to the actual EAF installation.

As mentioned above, the installation of the EAF was straightforward by simply following the instructions. Whilst most of us just know the reason for flats on spindles, I feel it was a bit remiss of the instruction not to mention this at any point and that at least one of the two securing grub screws on each end should make full contact with the flat. There was no mention either of the second grub screw lock, which should also be tightened. A further point to note is that you are directed to "download and read the detailed installation guide from the ZWO website before starting installation". The download unfortunately is for the previous 12v model, not this one, though much of the information is valid.

All in all, a great purchase, well worth the five stars given. I have not tried the software as I will be using this through alternative to the ZWO offering.

Rating (max 5):  
Works well
01 November 2022  | 

Got this delivered promptly and eagerly fitted it to my scope, then had to wait until the clouds cleared (usual event here in the UK). Well, I had a clear night and initially setup the backlash following a couple of YouTube videos, which seemed to work a treat. Next came the real test the auto focus (via NINA) which was performed without a hitch and managed to get R squared values in excess of 95%, so overall this was one of my better purchases and makes my imaging more convenient and fun.

Rating (max 5):  
Great for controlling a telescope using Remote Desktop
27 October 2022  | 

I originally got this primarily to do remote focusing (via Remote Desktop). It turns out it also makes focusing much easier and more accurate, This is a really well made device with good software support.

I attached this to a 2-inch Starlight Instruments Feather Touch FTF2025BCR focuser. It was actually quite easy to attach. I simply removed the big focus lock screw at the bottom and the curved bottom surface of the focuser fit nicely in the curved groove on the ZWO mounting bracket. I then added three of the included washers onto the big focus screw and used it to hold the mounting bracket in place. The washers prevent the screw from locking the focuser when it is screwed in tightly. It worked perfectly. No need to remove the little screws that hold the rotating mechanism in place.

I sometimes use the ZWO EAF manually with the hand controller. In this case, I use a USB cable connected to a USB mobile phone charger to provide power.

Rating (max 5):  
Good Investment
12 October 2022  | 

This is a great piece of kit, especially when coupled with the ZWO temperature sensor. It only took me a couple of minutes to connect it to a WO FLT 91 refractor, and calibration in NINA was straightforward too (thanks largely to Patriot Astro for his YouTube tutorial). NINA plays well with the ZWO EAF and it's a piece of cake to incorporate autofocusing into an imaging session. All in all, this is well worth the money for pin-sharp focus.

Rating (max 5):  
21 September 2022  | 

Much easier to fit on a William Optic ZS73 than I thought it would be. Connects automatically to the ASI Air. Unfortunately, I cannot yet comment on actual use to do the lack of clear skies. Excellent service from the team at FLO as always.

Rating (max 5):  
EAF on 76EDPH = a prefect match!
26 August 2022  | 

Fast delivery from FLO, as usual, thanks guys for your amazing service! I installed the EAF to the SharpStar 76EDPH and did some tests inside to make sure everything is working well before going outside in the dark! No problem to attach the focuser, nor to control it with the AsiAir Pro. Great product, can't wait to give it its first light!

Read all 46 customer reviews...


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