| This Vixen ED 0.67x focal reducer converts Vixen 81mm, 103mm, and 115mm ED apochromatic refractors from f/7.7 systems to faster f/5.2 systems for wider field 35mm imaging and shorter exposure times. This reducer does not work for visual observing, as the telescope’s shortened effective focal length eliminates the back focus needed to use a star diagonal and eyepiece. In addition to being unusable for visual use, the 0.67x focal reducer cannot be used with the Vixen 80mm ED80SF refractor. This reducer effectively converts a 625mm f/7.7 ED81SWT refractor to a 419mm f/5.2 optical system. The 795mm f/7.7 ED103SWT is converted to a 533mm f/5.2 scope. The 890mm f/7.7 ED115SWT becomes a 596mm f/5.2 system.
For prime focus SLR photography with a Canon, Contax, Konica, Minolta, Nikon, Pentax, or 35mm Yashica camera, both an optional 60mm wide photo adapter (#DW3878) and an optional T-ring appropriate to your SLR camera brand are required. The outer bayonet portion of an optional T-ring is removed from the T-ring by loosening the three small set screws that hold the inner 42mm T-thread portion of the T-ring in place. The bayonet portion of the T-ring is then attached to an optional 60mm wide photo adapter using the same three set screws (the 42mm inner portion of the T-ring is saved for possible later reassembly with the bayonet portion), The focal reducer is then threaded onto the opposite side of the 60mm wide photo adapter and the whole assembly is in turn threaded onto the drawtube of your telescope (after unthreading the eyepiece adapter from the drawtube). Your camera body is attached to the bayonet side of the focal reducer/T-ring assembly and you’re ready to shoot. Canon EOS and Olympus cameras do not require the #DW3878 adapter and separate T-ring. There are special adapters available for these cameras (#DW3876 for Canon EOS and #DW3877 for Olympus) that already combine the functions of the separate 60mm adapter and T-ring.
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