New ZWO EFW 7x36mm

The new 36mm EFW (Electronic Filter Wheel) was independently developed by ZWO for astronomical mono cameras. With the larger body and the newly-added screw holes on the covers, it will give a much easier and more fixable way to connect to ASI cameras.

There are 7 slots inside the EFW and we recommend you use the ZWO 36mm LRGB and SHO filter set with it.

The body is CNC milled from an aircraft-graded aluminum block. It is made with high quality and thin with a thickness of only 20mm. The heart of the EFW uses quality stepmotors produced by NPM, Japan, which can be very trustworthy. When photographing, you can rotate the EFW in both counterclockwise or clockwise directions for filter selection. The whole operation process is rather convenient and efficient.

Compared to the original 36mm EFW, you may find the new EFW has a bigger size. The screw holes on the front and back covers shall not only allow us directly connect the 36mm EFW to the camera and bring the filters closer to the camera sensor, also make the it possible to match it with M68 OAG.

There is no need for multiple cables to power this filter wheel up, just one USB cable does the trick. The power consumption of this EFW is approximately 120mAh @5V, which can be operated from the Cooled CMOS’s USB hub.

All ZWO 36mm filters can be perfectly supported by this EFW. But if you use filters from third party, then please make sure the thickness of the filter should be between 1.5mm and 3.0mm (the thickness of the filter frame is 1.8mm).

What’s in the box?

Specifications for the darkening sets(4pcs):

External diameter: 88mm. Inner diameter: 55mm (2pcs) & 58mm (2pcs). Thickness: ≤0.2. 4pcs in total.
* The reason for including the darkening sets is to help solve the light leaking issue occurring in the gap of the filter wheel and camera.

How to install the darkening sets:

Mechanical diagram