How do I know if I need the ZWO M42 Sensor Tilt Plate?
If you notice that stars are sharp in the center of your images but appear stretched or out of focus in one or more corners, you likely have sensor tilt. This is most apparent in telescopes with fast focal ratios (f/5 or lower) and with larger sensors like the APS-C format found in the ZWO ASI2600. The M42 tilt plate provides the necessary adjustments to correct this and achieve a perfectly flat field.
Can I use the ZWO M42 plate to connect my M68 OAG to a refractor with an M42 focuser?
Yes, this is one of its primary functions. The ZWO M42 Sensor Tilt Plate is specifically designed to bridge the connection between ZWO's M68 OAG and a telescope that has a male M42x0.75 thread on the focuser drawtube. It allows you to build a fully threaded imaging train for guiding and filtering.
How much back focus does the ZWO M42 Sensor Tilt Plate consume?
The plate itself has a thickness of 5mm. You must account for this 5mm in your total back focus calculation. For flatteners and reducers that typically require 55mm of back focus, this plate will be one component of that total distance.
Is this plate compatible with cameras other than the ZWO ASI2600?
It is made for APS-C cameras such as the ASI2600, used with the ZWO M68 OAG and 2" EFW. Its M42 thread faces the telescope, so it does not thread onto a camera's T2 port. It is particularly useful for any camera with an APS-C or smaller sensor.
How do you adjust the tilt on the ZWO M42 plate?
The plate uses a push-pull screw system. You will typically see sets of small screws around the perimeter of the plate. To make an adjustment, you slightly loosen one screw (the "pull" screw) and then gently tighten the opposing screw (the "push" screw) to tilt the plate in that direction. The process involves taking test exposures and making small, iterative adjustments until the corner stars are sharp across the entire field.
Will the ZWO M42 Sensor Tilt Plate cause vignetting with a full-frame sensor?
The M42 Sensor Tilt Plate suits APS-C cameras such as the ASI2600 and is not intended for full-frame cameras. For a full-frame camera such as the ASI6200 or ASI2400, ZWO offers its M48, M54 and M68 Sensor Tilt Plates instead.
