There are three models of QHYOAG: QHYOAG-S, QHYOAG-M, and QHYOAG-L for different size sensors. Please use the chart on the Specifications tab to choose the correct size for your camera.
The main purpose of the Off-Axis Guider, or OAG, is to use the same optical path as the main camera. This avoids the problem of differential deflection that can occur when using a separate optical system for guiding. In the case of the OAG, a part of the image is picked-off from the edge of the imaging circle which does not block the main CCD. This method provides more accurate guiding and sharper images.
In addition to the connection with the A-series cameras, you can also use the various standard or optional accessories provided by QHYCCD to achieve complex and adaptable connections, including the use of the OAG as a stand alone unit, connection to QHY filter wheels, etc.
The QHYOAG includes a precision 1.25-inch helical focuser that accepts our QHY5II and QHY5III cameras. The focusing process is comfortable. After focusing, you can lock the focus mechanism with thumbscrews. The QHYOAG is a thin and solid design. The OAG main body is just 10mm thick. Adding an M42 thread or M54 adapter ring adds only 3mm for a total thickness of 13mm.
There are six 3mm through holes in the OAG for direct connection to the QHYCFW2 and QHY "A" series cameras. If you do not have a QHYCFW2 or QHY "A" series camera, you can also use this OAG with a third-party adapter ring on the camera side.
The QHYOAG comes with a multi-threaded 1.25-inch focuser. The focuser has a locking thumbscrew to hold the guide camera fixed after focusing. The prism position can be adjusted and can be locked to fix its position. The prism is 8mm x 8mm size and the aperture between the prism and mirror is 8mm in diameter.