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Our new reducer, calculated and designed from Riccardi

Massimo Riccardi, famous optical designer from Italy, designed for APM-Telescopes a new 3 element 0.75 x Apo-Reducer/Flattener Corrector for all TMB-APM-LZOS Apochromatic Telescopes. Tests show that it also works on Apos from other manufacturers as well. The reducer shortens the focal length by a quarter and corrects the image circle - thereby converting your telescope into a fast astrograph!


The connection to your telescope and camera occurs over an M63 x 1 thread. For the correct adjustment of the reducer/flatener we can offer you an adjustment flange.


Usually the reducer is screwed onto the focuser. The reducer can also be installed inside the focuser barrel, if the free aperture is equal to or larger than 68 mm.

The right backfocus for your telescope you will find in the enclosed PDF chart (see below). The total optical path of reducer plus backfocus plus focus change is between about 160 mm and 180 mm.

The correction is made for chips up to the full-format and perfect for the best known Kodak KAF 8300 chip.

Connection to camera: M63 x 1 ID-Thread
Connection to telescope: M63 x 1 OD-Thread
Coating: Fully multicoated
Housing material: Aluminium
Recommended distance from focal plane to connecting thread: watch PDF
Focal length reduction: 0.75 x
Lenses: 3 Lenses
Optical length without collimation flange: 180.05 mm
Optical length with collimation flange: 189.05 mm
Fully corrected field: 40 mm
Length: 71.7 mm (with Dustcaps 75 mm)
Diameter: 67 mm
Weight: 17.5 oz (with Dustcaps 18.9 oz)