This Off-Axis Guider is for for QHY(IC)16803 and QHYCFW2-L and comes in three versions to accommodate image sensors of various sizes. With the same body as all QHY Off-Axis Guiders, it includes a prism, but the telescope/camera interface is sized to accept thread adapters of different diameters. Regardless of the diameter of the interface, it has six 3 mm holes and, without adapters installed, a thickness of 10 mm. Both the telescope side and camera side adapters have a thickness of 3 mm. The final thickness of the OAG depends on whether you need to use just the telescope side thread adapter or both adapters. If you are using the QHYCFW2-L, for instance, it will connect directly to the OAG-L, and you won’t need to use the camera side adapter.
The Large version of the QHY OAG has a diameter of 68 mm and will accept M42 x 0.75, M54 x 0.75, and M60 x 0.75 adapters. It will work with cameras that have larger sensors, such as CCD sensors which are 37 x 37, 36.24 or 48 x 36, (although the 50100, which has a 48 x 36 sensor, would require a special adapter, which is not included in this package.)
The QHYOAG-L has an 8 mm x 8 mm multi-coated prism. Its position can be adjusted as desired and then locked into position with a thumbscrew. It also comes with a locking multi-thread 1.25-inch focuser with an approximate range of 6 mm. If you use the QHY5L-II as your guide camera, its position is adjustable when inserted into the QHYOAG-L. These two adjustments will give you a wide range of back focus.
Please Note: Choose the Medium version of the OAG if you want to use a camera with an APS-C, APS-H or 36×24 sensor, such as the QHY(IC)16200A, or you have the QHYCFW2-M filter wheel.