The APM small reducer, designed by Massimo Riccardi, is an outstanding quality photographic accessory.
This Reducer will connect directly to APM or other 2.5" focusers which have an M63 thread. This reducer is suitable for use with refractors from 80/480 to 152/1200 and the GSO 10" Ritchey Chretien reflector.
The Reducer has a corrected field of 42mm permitting use with sensors up to this size. Using the Reducer will decrease focal length by x0.75 and increase image brightness. An APM 107/700 f6.5 will therefore become a 107/525 f4.9. The Reducer maintains a perfectly flat field following reduction. Reducers are designed to operate with specific telescopes and are not interchangable due to the critical nature of the optics unless a second scope falls within the tolerance of the reducer. For this reason please contact us with details about your telescope prior to ordering.
Also important is the back focus distance from the reducer to the camera sensor to provide a flat field. This will vary depending on the telescope. We can advise the correct distance to use and if necessary supply the required extension tubes.
The Riccardi Reducer is perhaps the bast value Reducer available today offering superb quality with a triplet lens cell using ED glass for true APO performance at a realistic price.