Astronomy Specialist

ZWO EFW 7 x 36mm

$529.00 AUD



The new ZWO Electronic Filter Wheel 7 x 36mm features a larger body and newly-added screw holes to give you a more flexible way of connecting ASI cameras such as the ASI2600MM Pro.

The EFW 7 x 36mm is CNC machined and has an optical thickness of only 20mm. High quality stepper motors from NPM Japan make this a very reliable solution. This model can take 7 x 36mm unmounted filters.

The power absorption of the EFW is only 120mAh @ 5V so any USB cable can power it up.



How to install the filters?

To install 36mm filters:

  1. Take the back cover off
  2. Lay the wheel down flat
  3. Hold the filters by the very edges and lay them on the filter wheel slots
  4. Lock each filter with a "mask" and a set of M2 screws
  5. Put the cover back on

To use the filter wheel:

  1. Install the ASCOM driver on your computer
  2. Plug in the USB2.0 cable
  3. On the Ascom options, select ZWO filter wheel (1) or ZWO Filter Wheel (2). There are two options to allow 2 filter wheels at the same time. 


The EFW 7 x 36mm filter wheels come with darkening rings intended to prevent light leaks due to the small gaps between the filter wheel and camera or OAG. The below diagram shows where to install them:



Compatible filters 7 x 36mm unmounted
Power draw 120 mA @ 5A
Power supply USB cable
Maximum thickness of the filter 3 mm
Optical thickness 20 mm
Camera connection
Direct screw connection to camera with tilt plate removed
Telescope connection M42 x 0.75 female
Camera compatibility APS-C and smaller ASI cooled cameras or cameras with a male M42 x 0.75 thread
Weight 555 g




    1. 7 x 36mm EFW body
    2. 1.25″ cover
    3. 1.25" T2 nosepiece
    4. 1.25″ holder (with cover and 2 screws)
    5. T2-T2 adapter (male)
    6. Filter masks
    7. USB 2.0 cable (2m)
    8. Phillips head screwdriver
    9. M2 x 4 flat screws
    10. Darkening ring set



    55mm backfocus with APS-C cooled camera and standard OAG



    55mm backfocus with APS-C cooled camera and OAG-L



    55mm backfocus with APS-C cooled camera and no OAG (M42m-M48f 22.5mm extender sold separately)


    ZWO EFW 7 x 36mm.

    ZWO EFW 7 x 36mm

    $529.00 AUD

    Optical design

    Image circle

    Focal ratio


    Focal length

    Optical thickness



    Colour or Mono

    Pixel size

    Sensor dimensions


    Sensor diagonal

    Quantum efficiency

    Read noise

    Fullwell capacity

    Bit depth


    Camera backfocus

    Filter size

    36 mm

    Filter size

    36 mm

    Bandpass (FWHM)

    Bandpass (FWHM)

    Glass thickness

    Mount type

    Payload capacity

    Latitude range

    Dovetail saddle

    Slew speed


    Periodic error correction

    Counterweight shaft

    Azimuth adjustment range

    Internal diameter

    Illuminated diameter

    Compatible telescope external diameter





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