ZWO OAG-L Off-Axis Guider Large for ASI Full Frame Cameras
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Vai al moduloThe ZWO OAG-L (Off-Axis Guider Large) is ZWO's large-format off-axis guider designed for long focal length astrophotography with full-frame cameras. Compared to the standard OAG, the larger prism (12×12 mm) intercepts a greater portion of the telescope's light cone, providing a wider field of view for the guide camera and a higher chance of finding suitable guide stars even in sparse star fields. No guide scope, no differential flexure: the guide star comes from the same optical path as the main camera.
Full-frame off-axis guiding: zero differential flexure
A prism diverts a small portion of the peripheral light to the guide camera, which monitors a star in the same optical field as the main camera. The result is extremely precise guiding, free from the differential flexure typical of separate guide tube setups. The OAG-L is designed specifically for full-frame cameras and high-resolution imaging at long focal lengths.
Optical path and compatibility
Telescope-side connection: M48×0.75 (internal thread); camera-side: 2". Supplied with an M48 tilt plate already fitted, allowing precise alignment of the focal plane with the camera sensor. Total optical path with tilt adapter (5 mm) + optional EFW (20 mm) + optional cooled camera (12.5 mm): 55 mm. For guiding, the OAG-L is compatible only with ASI Mini cameras (ASI174MM Mini, ASI290MM Mini, ASI120MM Mini).
Integration with EFW series and cooled ASI cameras
The OAG-L is designed to work with ZWO EFW filter wheels, forming a compact integrated optical train. Without an EFW, the ZWO D70-M54F adapter is required to achieve the correct 55 mm backfocus. The reference solution for full-frame cooled cameras such as ASI6200MM, ASI2600MM or ASI294MM Pro on long focal length telescopes.
Technical specifications
| Telescope-side connection | M48×0.75 (internal thread) |
|---|---|
| Camera-side connection | 2" |
| Prism size | 12×12 mm |
| Optical length | 1.5 mm / 22.5 mm |
| Total backfocus (tilt + EFW + camera) | 55 mm |
| Included adapter | M48 tilt plate |
| Compatible guide camera | ASI Mini (ASI120MM, ASI174MM, ASI290MM Mini) |
| Supported sensor format | Full Frame |
| Manufacturer | ZWO (Suzhou ZWO Co., Ltd.) |