10 of 14 people found the following review helpful
An engineering marvel,
This review is from: Opteka T-Mount Adapter for Canon EOS 70D, 60D, 50D, 40D, 30D, 20D, 7D, 6D, 5D, 1D, Rebel T5i, T5, T4i, T3i, T3, T2i, T1i, XS, XSi, XTi and XT Digital SLR Cameras (Electronics)
The creator of this adapter managed to magnificently capture every detail which makes this product as ill equipped to handle its job as possible, then incorporated them all into two pieces, and slapped them together with the smallest screws possible. Following this philosophy, the manufacturer chose to sell this adapter without tightening the screws.
This adapter consists of two pieces, an outer 'main' part which is appropriately keyed to fit select Canon cameras and a thin, threaded insert. The entire system relies on three extremely small screws to 1.) prevent the lens from pulling away from the camera body, and 2.) prevent the lens housing from rotating while turning the focus ring.
Although this adapter is a true marvel of engineering failure, I can attest to Opteka's commitment to quality. When they sent me the wrong adapter in the Opteka 500mm Canon mirror lens/T-mount adapter kit, I noticed the Nikon version of this adapter was surprisingly well made before sending it back and receiving this trash for my Canon 550D.
Update: A screw driver from a cheap eyeglass repair kit was enough to fix this mount. I've been able to use it several times and although I still believe the mount is designed poorly, it does serve its purpose moderately well when the screws are tight.