Celestron T-ring for 35mm Nikon cameras

Celestron T-ring for 35mm Nikon cameras

Fits all SLR cameras with Nikon bayonet
the T-ring connects your 35mm camera body (SLR cameras) to a T-adapter, an off-axis guider or a tele-extender
To use a T-ring you will need to remove the star diagonal and/or eyepiece from your telescope (some models require an eyepiece - see your instrument manual for details). Then all you have to do is replace your camera lens with the T-ring and attach this combination to the end of your telescope using the Celestron T-adapter
Focal photography with telescopes

With a T-ring, your telescope or spotting scope becomes a telephoto lens. Instead of the camera lens, the T-adapter is simply connected to the camera body and the camera can be screwed tightly to the optics. Many telescopes already have a T2 thread (M42x0.75) integrated into the focuser ex works, for all others there are suitable adapters to a 2" plug-in size. The telescope then works like a telephoto lens with a fixed aperture and manual focusing that corresponds to the focal length (To estimate the image section, you may have to take the crop factor of the camera sensor into account.) In order for the images to be successful, the focuser should be as robust as possible (image on the right), focusing is best done using the live view mode of the camera, so even long focal lengths can be precisely focused.

All Celestron T-rings are standardized so that the distance from the contact surface to the camera sensor is 55.0mm. In this way, the distance to other optical accessories such as field flatteners or Barlow lenses can be maintained exactly so that no avoidable image errors occur.

The Celestron T-Ring for Nikon fits all SLR cameras with a Nikon bayonet.


With a T-ring, the telescope becomes a telephoto lens. A solid focuser is a must for photography.
With a T-ring, a reflex camera can not only be connected to a telescope, but also to many spotting scopes or suitable eyepieces. With spotting scopes, the camera is not connected directly to the spotting scope, but to the eyepiece. With the so-called eyepiece projection, the magnification is higher and depends on the magnification of the eyepiece. Direct connection to a spotting scope is usually not possible, at least with refractor scopes, since the camera cannot be focused. The eyepiece projection circumvents this problem.

40mm T2 extension sleeves have proven their worth for better image sharpness; these increase the magnification even further.

Due to the stable screw connection, even heavy SLR cameras are held securely; while a universal camera mount (MicroStage) is sufficient for small compact cameras.

This method of eyepiece projection is qualitatively the best way to photograph through a spotting scope and has been the standard method for planetary photography in amateur astronomy for years, as it allows the necessary high magnifications to be easily achieved.


Many spotting scopes like the Celestron Ultima 80 here have a T2 thread integrated in the eyepiece.
A T-ring connects your 35mm camera body to a T-adapter, off-axis guider or tele-extender. You need it to photograph through a telescope or spotting scope.


Manufacturer Celestron
Item number (#) 820834
EAN code 4047825003126
Net weight (kg) 0.03
Optical length (mm) 8
Intended use for connecting (D)SLR cameras to the Astro T-2 thread
Camera connector Nikon
Inside diameter / free opening (mm) 40
Outside diameter (mm) 55
Internal connection (telescope side) thread
External connection (eyepiece/camera side) bayonet