The EAF focuser can be used for deep sky astrophotography and for planetary/lunar imaging and supports focusing using both manual and autofocus modes.

For deep sky photography, the user may use either manual or software autofocusing, while planetary photographers may only use manual focusing at this time.

Let’s take a look at how you can use your EAF to improve your telescope focusing.


Manual focus using EAF

There are two ways to focus manually:

Mode 1 allows you to focus using the hand paddle available as part of the advanced EAF kit or purchased as an optional extra if own the standard kit. Plugging the hand paddle into the EAF allows you to control the position and speed of the focus motor manually using the paddle buttons.

Mode 2 allows you to focus using your favourite capture software. The tools used in both modes are different, but the methods are exactly the same.

Taking the ASICAP capture software and ASIAIR controller as examples; this document describes how to achieve focus using your EAF.

When attempting to setup your EAF for the first time we strongly recommended that you do this in the daylight and with telescope aimed at a distant building or structure such as a TV antenna or radio mast. This will allow you to easily find the right position and ensure you are in a good position to achieve focus when venturing under the stars at night.

Once you have achieved a good focus in the daylight you should record the stepper position and then when using the telescope in the dark at night, you can go directly to the last focus position you recorded above and continue with the instructions below.

ASICAP manual focus

Step 1: Finding a rough focus position


Step 2: Fine-tuning your focus position


Step 3: Focus achieved – success!


Step 4: After shooting, the EAF returns to zero position.ASICAP_manual_focus_4

ASIAIR Manual Focus

Step 1: Finding a rough focus position


Step 2: Fine-tuning the focus position


Step 3: Focus Achieved – Success!


Step 4: After shooting, the EAF returns to zero position.


The manual focus capability of your EAF improves the speed and accuracy of trying to achieve that perfect focus. This is really helpful when doing planetary or lunar photography. For deep sky astrophotography a similar method as shown above can be used, but you can also use a software driven autofocus method which is generally quicker and more accurate than using the hand paddle methods.

28 Responses to How to Use Manual focusing with EAF
  1. Avatar

    Intento instalar el EAF en el Baader Diamond Steeltrack Focuser y no es posible !


  2. Avatar

    Will the ZWO EAF work with N.I.N.A?


  3. Avatar

    I have the older EAF 12 volt with temp sensor. I cannot get the amount of steps needed to focus my Celestron c11 edge for the full focus length needed, there is not enough steps that can be set to achieve this and I cannot move the focuser to go in the negative to make up what would help me


  4. Avatar

    Can I use hand knob on my focuser to focus or is it only through the software once installed?


  5. Avatar

    We are now into the last quarter of 2020. When will autofocus be included in the ASI Air PRO? The closed system is incomplete without this feature.


  6. Avatar

    I realy don’t know what’s going on the autofocusing in asi air(not pro version)

    you mean I can’t use my eaf’s autofocusing? possilbe menual focusing only?


  7. Avatar

    Did just buy ZWO EAF and very disappointed that AUTOFOCUS with ASIAIR PRO is nog working since not yet available !!
    very disappointed


    • Avatar

      We are sorry about this! Our developers are working hard to develop this feature. Please wait. And before this, you could use other software which has auto focus to achieve auto focus.


  8. Avatar

    how it works the auto focus via ASIAIR software? Or it’s still impossible?


  9. Avatar

    Just bought the ZWO EAF Advanced… drivers installed and I am able to control it…l BUT:

    How do I use the hand paddle controller… it is not responding, I doubt it is defective, more like operator error… I tried connected and disconnected with my software, SGP… but no luck.., any suggestions?


  10. Avatar

    I find it extremely annoying that you cannot focus manually by hand when the EAF is installed. Sometimes I just use my scope visually on a manual Alt-Az mount w/o being connected to power or a PC.
    There are motor focusers which allow you to still focus manually. Why not this one? 😒


  11. Avatar

    If the zero point is set to 0 and you want to move the focuser inward further than the set zero point… you can’t. Resetting the device, uninstalling drivers etc will not reset and allow the zero point to be made at a different location!!


  12. Avatar


    how it works the auto focus via ASIAIR software? Do you have any user manual for this point?

    Thanks for your Information!

    Andreas Corente




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