If you have a Canon EOS DSLR camera and want to connect it to a telescope, reducer/flattener, or use a lens with a T-2 male thread, you will need an EOS T-ring. However a standard T-ring uses T-2 threads but a lot of reducers/flatteners use M48 threads. Also what do you do if you also want to use filters such as H-alpha? Baader Planetarium have the answer – their Baader Zero Tolerance Protective Canon EOS T-Ring! So what is it?
- Zero Tolerance: Cheap T-rings can provide a poor (“loose”) connection with the body of the camera. Baader have carefully examined the mating between the T-ring and the camera body bayonet to produce a T-ring which is both “wobble free” and also has no lateral play. This means that when locked into position, this Baader T-ring helps create a stable imaging interface between camera and telescope/lens with no camera body “flop”, even during long exposures or when the telescope slews from object to object, keeping your images sharp.
- Protective: Standard T-rings allow the inside of the camera to be exposed to the elements once the camera is removed from a telescope or lens. The protective T-ring allows Baader and other 2″ mounted and 50.4mm unmounted filters to be placed inside the T-ring body. The fitment of a filter helps protect the camera sensor from becoming dirty leading to dust spots and spoiling your images. Also having the filter located inside the T-ring means that it does not affect connections to e.g. reducers/flatteners, extension tubes etc. All Baader 50.4mm unmounted and 2″ filters mounted in low-profile filter cells (LPFC) may be used with the Protective T-ring.

The Baader Zero Tolerance Protective Canon EOS T-Ring with the S52-to-M48 adaptor ring and a filter in place.
- Connectivity: The Protective EOS T-ring offers four different connections to allow your camera to be attached to a wide variety of telescopes and accessories. The T-ring uses Baader’s S52 dovetail which allows it (without any of the other supplied adaptors) to be easily and securely used on e.g. Baader Universal Filter Changer (UFC) with the S52 UFC dovetail camera-side adaptor. It also comes with an S52-to-2″ nosepiece for straight push fit connection into a 2″ focuser, an S52-to-M48 (female) adaptor and an M48-to-T-2 (female) adaptor allowing the Baader Astro T-2 system to be used for many other types of mounting onto a wide range of accessories.

The Baader Zero Tolerance Protective Canon EOS T-Ring parts supplied (unmounted filter is an option and not included in the T-Ring only option)
- Filter options: The Baader Protective T-ring is available on its own (if you already have filters) or is available with Baader 50.4mm unmounted 3mm thickness Clear, UHC-S, UV/IR Cut Filter and 7nm H-alpha filters.

The Baader Zero Tolerance Protective Canon EOS T-Ring with S52-2″ nosepiece and the available filter options.
We’ll take a closer look at this Baader Protective Canon EOS T-Ring in a future blog.
You can read more about this item here, and it is available from ourselves or one of our authorised Baader Planetarium stockists.