ASI071MC Pro back focus
ZWO specify “The M42 female flange to the sensor is 17.5mm”. That is measured to the camera's own front face, with no adapters fitted.
- Back focus
- 17.5 mm
- Thread
- M42
- Sensor
- 23.6 × 15.6 mm
- Pixel size
- 4.78 µm
- Type
- Colour, cooled
Checked against the manufacturer’s documentation in September 2026.
Where to buy the ZWO ASI071MC Pro
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Telescopes
| Telescope | Back focus | Spacers | Sampling | Result |
|---|---|---|---|---|
| 103APO | 55.0 mm | 21.0 mm | 1.76″/px | Exact |
| 185APO | 55.0 mm | 21.0 mm | 0.95″/px | Exact |
| FRA400 | 55.0 mm | 21.0 mm | 3.52″/px | Exact |
| FRA500 | 55.0 mm | 21.0 mm | 2.82″/px | Exact |
| FRA600 | 55.0 mm | 21.0 mm | 2.35″/px | Exact |
| Evolux 62ED | 55.0 mm | 21.0 mm | 2.74″/px | Exact |
| Evolux 82ED | 55.0 mm | 21.0 mm | 2.07″/px | Exact |
| Evostar 100ED | 55.0 mm | 21.0 mm | 1.29″/px | Exact |
| Evostar 120ED | 55.0 mm | 21.0 mm | 1.29″/px | Exact |
| Evostar 80ED | 55.0 mm | 21.0 mm | 1.93″/px | Exact |
| Fluorostar 91 | 60.4 mm | 26.4 mm | 2.28″/px | Exact |
| Gran Turismo 71 | 64.1 mm | 30.1 mm | 2.94″/px | Exact |
| Gran Turismo 81 | 62.1 mm | 28.1 mm | 2.58″/px | Exact |
| Zenithstar 61 | 56.0 mm | 22.0 mm | 3.42″/px | Exact |
| Zenithstar 81 | 60.2 mm | 26.2 mm | 2.20″/px | Exact |