The Celestron EdgeHD telescopes are great for astrophotography. A lot of people who own one of these larger EdgeHD telescopes, and do astroimaging, may think there is just one T-adaptor available that allows them to attach their camera to their telescope. However…..Celestron actually do two.
The standard EdgeHD T-adaptor for the 9.25″,11″ and 14″ models is manufactured with a 42mm T-thread on the camera side. This Celestron adaptor, and the standard T-rings if used, are fine for use with APS-C sized DSLR’s and Mirrorless cameras or imaging cameras with small imaging sensors. However for those that have, or want to use a camera with a larger format full frame sensor, such as a full-frame DSLR, then Celestron’s 48mm EdgeHD T-adaptor is the one to go for.
The best way to understand why this is, is to look at image below. This shows the difference between using a standard T-ring versus an M48 wide T-ring with a camera fitted with a full frame chip.
- The image below left shows a standard M-42 T-ring attached to the camera body. It can be seen that the inside of the T-adaptor “cuts off the corners” of the sensor leading to reduced illumination (vignetting).
- The image below right shows an M48 T-ring attached to a camera. The wider inside diameter of the M48 T-ring does not interfere with the edges of the imaging sensor.
So if you have a small sensor camera (e.g. APS-C DSLR) the standard EdgeHD T-Adaptor (42mm) is fine and the product code for that adaptor is #93646.
If you require the M48 wide T-Adaptor the code, we have discussed here, the product code you need to ask for, or order, is #93622. You will also need a wide T-ring specific for your DSLR camera too.
The wide Celestron T-adaptor, and wide T-rings, can be obtained from your local or favourite astronomy retailer.