How does the ZWO T2-1.25" Adapter affect my back focus?
The adapter is 3 mm thick, but because it threads into the camera or adapter it adds only 1 mm of length to your imaging train. This is a minimal distance designed to preserve the critical back focus required by most optical correctors like field flatteners or coma correctors.
Will this ZWO adapter work with non-ZWO cameras and filters?
Yes. The adapter uses the universal M42 (T2) thread standard on the camera side and accepts any standard 1.25" astronomy filter. It is compatible with any T-threaded astronomy camera and any brand of 1.25" filter.
Can I use the ZWO T2-1.25" Adapter with a filter wheel?
No, this adapter is designed as an alternative to a filter wheel for single-filter applications. It threads inside an adapter, often the 11mm T2 extender, so the 1.25" filter sits inside the optical train near the sensor, which prevents vignetting. It is ideal for monochrome guide cameras or for color cameras where you only need to add a single light pollution or UV/IR cut filter.
What is the advantage of this adapter over a 1.25" nosepiece with filter threads?
The primary advantage is rigidity. A direct M42 thread connection prevents the tilt and sag that can occur with a nosepiece held in place by thumbscrews. This secure, parallel connection is crucial for avoiding image degradation, especially with sensitive optical systems.
Is the ZWO T2-1.25" Adapter a good choice for adding a UV/IR cut filter to my ASI178MC for lunar imaging?
Absolutely. For planetary, lunar, or solar imaging with a one-shot-color camera like the ASI178MC, adding a single UV/IR cut filter is critical for sharp focus. This 1 mm adapter provides the most secure and lowest-profile method to do so without altering your setup significantly.
How do I tighten the ZWO T2-1.25" Adapter?
The adapter has four small holes on its face. While it can often be tightened by hand, if you need extra leverage, you can use a spanner wrench or the tips of a small pair of needle-nose pliers inserted into two opposing holes to gently secure it to your camera body.
