01.04 · Provisional page
ZWO EFW
Filter wheel; automated filter selection
The ZWO EFW 7 × 36 mm is the motorised filter wheel I use with 36 mm Astronomik filters. It is the black circular body immediately in front of the main camera: it holds up to seven filters and allows the capture software to select the required one automatically for each exposure. Keeping the filters close to the sensor helps reduce the risk of vignetting, while its slim 20 mm body makes it easier to maintain the correct spacing between components. A single USB cable provides both power and control, with a maximum consumption of approximately 150 mA, so it can connect directly to the camera’s USB hub or the hub installed on the telescope. Its machined aluminium enclosure combines rigidity with a weight below 400 g.
Imaging train
Technical specifications
- Capacity
- 7 unmounted 36 mm filters
- Filters used
- 36 mm Astronomik filters
- Telescope connection
- Female T2 thread
- Camera connection
- Male T2 thread
- Additional connection
- 1.25″ through the supplied adapter
- Optical thickness
- 20 mm from T2 to T2
- Power and control
- Single USB cable · approx. 150 mA maximum consumption
- Construction
- CNC-machined aluminium enclosure
- Weight
- Below 400 g
