Adapters to attach ASI 294 MC to Canon 135mm lens?

rbaccus

What adapters do I need to achieve focus with the 294 MC camera using the Canon lens zoomed to 135 mm? Here is the hardware I have (see attached image). I have tried with and without the 16mm extension and have not been able to achieve focus with the lens at 135 mm. Do I need some other adapter or extension? Thanks in advance,

Ronny

IMG_5543.jpg

Support@ZWO

Are you using this adapter? Please follow the guide on the link and remove the 20mm extender.

https://astronomy-imaging-camera.com/product/eos-t2-%e2%85%a1-adapter-suitable-for-all-asi-cameras

rbaccus

I have the Canon EFS 18-135mm lens along with the ZWO T2 Thread to Canon EOS Lens Adapter for all ASI Cameras # T2-EOS (which appears to match the link you provided). I have not been using the 21mm extender shown in the first image, just included that for reference in case I needed it.

The adapter works with the camera when the lens is zoomed out to the short focal length, but when I zoom to the higher focal length I cannot achieve focus. The adapter is in two parts, with one part being an 15mm long extender that also changes from large to smaller thread diameter that will thread into the camera. Removing this extension from the adapter (as shown in this image below) leaves the lens adapter with a thread diameter that will not interface with the 294 MC camera body (adapter thread diameter is too large). What am I missing?

Support@ZWO

EOS-T2 adapter without T2-extender is suitable for 17.5mm back focus distance ASI cameras such as Cooled cameras and ASI174 ASI294 ASI183 ASI1600 ASI533 ASI2600 except for ASI6200 and ASI2400.

Please remove the 11mm ring and T2-extender.