ZWO EFW 5 x 2" / 7 x 2"
ZWO developed two filter wheels for 2" filters. Cameras with large sensors such as the ASI 6200 require 2" filter to avoid any vignetting.
These electronic filter wheels are CNC machined and they have an optical thickness of only 20mm.
There are two models available:
- type 1: 5 filters x 2″ mounted
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type 2: 7 filters x 2" mounted
The power absorption of the EFW is only 120mAh @ 5V so any USB cable can power it up. The distance between the filter and sensor of the ASI 6200 is only 18 mm.
Unmounted filters with a diameter of 50.4mm ± 0.5mm can be used in both filter wheels.
Mounted filters from third-parties producers can be used but they have to meet the following requirements:
| Compatible filters | 5 x 2" mounted / 7 x 2" mounted |
|---|---|
| Ports |
USB |
| Power draw | 120 mA @ 5A |
| Power supply | USB cable |
| Maximum thickness of the filter | 7.5 mm (not including threads which must be less than 2.7 mm) |
| Optical thickness | 20 mm |
| Camera connection |
Direct screw connection to camera with tilt plate removed, M54 x 0.75 |
| Telescope connection | M54 x 0.75 female |
| Camera compatibility | APS-C and larger ASI cooled cameras or cameras with a male M54 x 0.75 thread or compatible tilt plate |
| SKU | ZWO-EFW-5x2, ZWO-EFW-7x2 |
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55mm backfocus with 4/3" or 1" cooled cameras with T-2 Tilter
55mm backfocus with 4/3" or 1" cooled cameras with T-2 Tilter and OAG
55mm backfocus with APS-C cooled camera and standard OAG
55mm backfocus with full frame cooled camera and OAG-L
55mm backfocus with full frame cameras and no off-axis guider
Click here for detailed instructions for removing the sensor tilt plate and alternative setups.