The Celestron M42 Spacer Ring Kit allows you to set the proper back-focus distance between your telescope and imaging rig. Getting the correct distance is critical for tack-sharp images—if it's not exactly correct, the corners of full frame imaging sensors will suffer and stars will appear elongated instead of as pinpoints. The kit comes with 7.5mm, 12mm, and 30mm rings with standard male and female T-threads that allow you to use them individually or stacked in any combination and then married to your camera-side T-ring and telescope-side T-adapter without the need for converter rings. Made of anodized aluminum and treated with a black anodized finish, the internal surfaces are blackened and threaded for glare reduction to provide improved image contrast.

Made for Astroimaging Rigs    Adjusts Back-Focus Distance    7.5mm, 12mm, and 30mm Rings    Standard Male & Female T-Threads    Black Anodized Aluminum

Related Questions and Answers

Q: 1. Can I attach this to the Ef to RF adapter for use on my R6?

A: You need to use an RF T-mount adapter, like this one: https://www.bhphotovideo.com/c/product/1494990-REG/vivitar_hf_t2_eos_r_t_mount_to_canon_rf_mount.html

Q: 2. Is this the adapter to mount Nikon DSLR D7000 to Celestron TrailSeeker 100 22-67x100 Spotting Scope?

A: The Celestron T-Mount SLR Camera Adapter for Nikon F-Mount needs to be connected to an actual T mount, such as https://bhpho.to/2UfejnB , the normal T-mount diameter is 1.25 of an inch, and will fit the Celestron Spotting Scope eyepiece tube instead of an "eyepiece". After connecting the Celestron adapter to a T-moun, then one would connect the Nikon D7000 to the newly assembled T-mount on the F mount adapter side. It is important to keep in mind if you replace the eyepiece with a camera the magnification of the eyepiece will be reduced to 1X. Many people today prefer to shoot a photo through the eyepeice to retain the magnification.

Q: 3. Is this the 10mm T ring?

A: The T-Ring is 11mm. Canon EOS (EF) bodies are 44mm deep, and adding an 11mm T-ring will get you to the ideal 55mm spacing.

Q: 4. Does this have M42 or M48 thread?

A: T-mount are typically M42.

Q: 5. it is unclear to me how this adapter attaches to the telescope eyepiece. Do I need anything in addition to this item?

A: The Celestron T-Ring for Nikon F-Mount Cameras changes the camera lens mount to a T-mount. This would then need an adapter on the Telescope side to change the telescope to a T-mount as well. Basically this adapter is half the picture, one needs an adapter on the telescope side as well, as most are not native T-mount.

Q: 6. I have a eos m50 mirrorless camera. Please help how mount 420-800 Andoer lens. Thanks

A: The Celestron T-Mount SLR Camera Adapter for Canon EOS #93419 only works on the EF-mount, not the EOS-M-mount or the RF-mount mirrorless cameras. You will need a Canon or third party EOS-M to EF mount adapter that will fit to our #93419. Sincerely, Garrett at Celestron

Q: 7. Is the 10mm t ring?

A: The Celestron T-Mount SLR Camera Adapter for Canon EOS is a standard T-mount adapter.

Q: 8. Follow-up Question: how does it attach to the scope? Does it come with set screws?

A: This T-ring attaches to your Nikon-F mount body in place of the lens. Ti mounts on to the camera just as your lens did. I should attach to a "camera adapter" mounted on the specific make and model of your telescope or spotting scope.

Q: 9. used with Rebel cameras do I also need an EF-S to EOS adapter?

A: Nope! This will work with EF and EF-S cameras without an adapter. You will only need another adapter if you have the mirrorless line of Canon cameras, the EF-M.

Q: 10. Will this work w/ a D750?

A: Yes. It will work for any F Mount. Works with my D600.