Why use a restrictive T-Ring, when you can let every photon of light through with this true 2" prime focus adapter?
The ELIM-T adapter from Blue Fireball Technologies can reduce vignetting and increase the field of view, while eliminating the need for a separate T-Ring when using a DSLR camera for prime focus imaging. The adapter fits onto a DSLR camera body, and inserts directly into a 2" focuser or accessory. By attaching to the camera directly, the adapter provides an unobstructed aperture of 47.5mm (1.87"), up to 10mm more than with a conventional T-Ring. This is the largest clear aperture of any adapter on the market today!
The ELIM-T is threaded for 2" filters, and baffled to reduce internal light reflections. The chrome barrel has a safety groove for added protection in case your focuser thumb screw should come loose. All metal construction.
For all Nikon Film SLR or Digital DSLR cameras including D1, D2, D3, D3S, D3X, D35, D40, D40X, D50, D60, D70, D80, D90, D100, D200, D300, D300S, D700, D3000, D3100, D5000, D7000, and others.
Weight = 2.1oz, Total Length = 2.17" (55mm), Length of Chrome Barrel = 1.54" (39mm).