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Stellarvue SV70T Focal Reducer and Field Flattener - SFFR-70APO

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Stellarvue Reducer/Flattener
for SV70T Triplet APO

The Stellarvue SFFR-70APO Reducer and Field Flattener is optimized for the Stellarvue SV70T and has a reduction ratio of 0.8X. It will convert the 70mm f/6 to a 336 mm f/4.8, making the SV70T a supreme wide field refractor. The reducer/flattener threads into the Stellarvue 2.5” A version focuser (standard on the SV70T). It will also slide into the 2” focuser on the earlier model SV70ED.

The SFFR-70APO has a standard 48 mm filter thread, allowing you to add 2" filters for imaging. The back focus of the unit is 55mm with the included 11 mm extension tube. Remove this tube and the back focus increases to 66mm. Since a DSLR with t-ring has 55mm of back focus, thread the Stellarvue SFFR-70APO and the included extension tube into the camera's t-ring, then screw it to the focuser in the Installation Instructions graphic to your left.

If you are using a CCD camera, an additional set of 42mm extension tubes may be needed depending on the back focus of your camera. You need to know how much distance there is between the camera's T-thread and the CCD chip. It is important that the distance from the back of the field flattener to the chip be maintained at 55 mm (66 mm without the supplied extension). So if the CCD camera has a back focus of only 35mm, the supplied 11mm extension and an additional 20mm extension will be needed. See the CCD Extension graphic to your left for a visual. A wide range of 42mm extension tubes is available from Stellarvue...we have attached them to our Accessories section for your perusal.