Esprit 150ED Reducer/Flattener (.77x)

36mm fully illuminated field, compatible with both APS-C and full frame sensors 90mm back-focus (55mm when back focus spacer and M48 ring installed) Drops f/ratio from native f/7 (1050mm) to f/5.4 (810mm) Reduces exposure time by 68% compared to native f/7 2.54 x 1.7-degree field of view when used with a full frame camera 1.66 x 1.11-degree field of view when used with APS-C crop sensor  Includes reducer, metal thread-on caps, back focus spacer and M48 thread adapter Built-in 2" filter cell for mounting filters into the light path