Tele Vue's T-Ring Adapter works perfectly with the 2" 4x Powermate for anyone who may be interested in astrophotography. All Tele Vue telescopes can be readily used as super-quality telephoto lenses for 35 mm SLR cameras. They can also be used with digital cameras by coupling the digital camera lens to certain Tele Vue eyepieces, using adapters that connect the eyepiece to the camera lens filter threads. For use with 35 mm cameras, you will also need a T-ring that mates to your particular model camera body. Replaces an eyepiece holder on PMT-4201 with T-ring threads for photography.