CELESTRON T-ADAPTER FOR SCHMIDT-CASSEGRAIN TELESCOPESThis sturdy metal T Adapter is the accessory of choice if youd like to attach an SLR or DSLR camera to the rear cell threads of a Schmidt Cassegrain telescope for prime focus photography. To get started, youll need the appropriate T Ring for your camera body (#93402 for Nikon & #93419 for Canon EOS). Remove the lens from your camera and attach the T ring in its place. Since the T ring is camera brand specific, it will snap right on just like a lens.