What do I need to connect my Canon EOS lens to a ZWO 2" EFW?
You need this specific adapter, the ZWO EOS Lens Adapter for 2" EFW (SKU: ZWO-EFW2-EOS). It has the correct M54x0.75 thread to attach directly to the 2" filter wheel.
Will this ZWO EOS adapter work with my ZWO 36mm EFW?
No. This adapter is exclusively for the ZWO 2" EFW. The ZWO 36mm, 31mm, and 1.25" filter wheels require the ZWO-EOS-T2 adapter, which uses a smaller M42 thread.
Do I need to modify my ZWO camera to install the EFW2-EOS adapter?
Yes, a minor adjustment is required. You must remove the sensor tilt adapter that comes pre-installed on the front of your ZWO cooled camera. This allows the camera to connect flush with the back of the 2" EFW.
Can I use this adapter to image the Orion Nebula (M42) with my ZWO ASI2600MC Pro camera?
Absolutely. This adapter is the ideal component for that setup. It allows you to connect a wide-angle Canon EOS lens to your 2" EFW, which would house your filters (like a dual-band filter), and then thread directly to your ASI2600MC Pro (after removing its tilt plate). This creates a powerful wide-field imaging rig perfect for large targets like the Orion Nebula (M42).
Why does this adapter use an M54x0.75 thread instead of a standard T2 thread?
The larger M54x0.75 thread is necessary to match the opening of the 2" EFW. A smaller T2 (M42x0.75) thread would create a bottleneck in the light path, causing significant vignetting (darkened corners) on cameras with large sensors, especially when using full-frame EOS lenses.
What is the warranty on the ZWO EFW2-EOS adapter?
This ZWO adapter is covered by a 2-year manufacturer warranty, ensuring it is free from defects in materials and workmanship.