The ZWO EFW motorized filter wheel features 8 × 1.25" or 31 mm diameter slots, allowing for motorized filter changes via a computer or with the help of ZWO ASIAir, ToupTek Stellavita. It is an excellent match for cameras with sensors up to 20 mm in diameter.
The filter wheel has T2 threads on both sides for telescope and camera attachment. Both sides of the product offer screw mounting options for the manufacturer's cooled cameras, allowing the filter wheel to be positioned closer to the camera sensor, reducing potential vignetting. It connects to a computer via a USB 2.0 port, and after installing the ASCOM driver, it can be controlled with any compatible software. The power supply for the filter wheel is also through the USB 2.0 port, so no additional cables are needed, just a single USB cable. The maximum current draw of the ZWO motorized filter wheel is approximately 120 mA @ 5V, enabling operation through the USB2.0 port of a cooled astro camera.
The ZWO EFW motorized filter wheel is housed in a high-quality aluminum casing, with a width of only 20 mm and a weight of 530 grams. Its slim design allows it to be placed surprisingly close to the camera sensor, so even with telescopes with a low focal ratio, vignetting is not a concern.
The updated filter wheel features a USB-C connector and has received additional "sealing" against stray light.
