ASKAR FRA400 F/5.6 APO REFRACTOR Nadirus 16" 1390 mm (extended)

1390 mm (extended)

3" Schmidt-Cassegrain male threads (11" SC/HD and 14" SC/HD) and holds 2" accessories

5e- at lowest gain (5

It is collimable by using 3 grub screws and the offset can be adjusted by using the central spring loaded screw

Any source of flex appears like being “magnified” 20-fold

ASKAR FRA400 F/5.6 APO REFRACTOR Nadirus 16" 1390 mm (extended)The Askar FRA 400 f 5. 6 is a professional apochromatic Petzval quintuplet with an aperture of 72mm and a corrected field of 44mm in diameter. The lenses are assembled in two groups: an air spaced triplet on the front and a correcting doublet towards the focus. The objective lens includes two Extra Low Dispersion glass for a superb chromatic correction. Differently from standard ED refractors, the Askar 400 features a Petzval design that does not