BAADER M68 EXTENSION TUBE Optical Thickness:100mm Best performance with F/7 -

Best performance with F/7 - F/30 refractors full aperture

Full-frame

25" / 2" mounted SKU BA2961580 (1

Optical design Ritchey-Chrétien Diameter 406 mm Focal length 3250 mm Focal ratio f/8 Linear obstruction 170 mm Corrected field 35 mm (70 mm with optional corrector) Backfocus distance 288 mm from rear cell Focuser thread M77 x 1 female

BAADER M68 EXTENSION TUBE Optical Thickness:100mm Best performance with F/7 -The Baader M68 extension tubes have male M68 x 1 threads on one side and female M68 x 1 threads on the other. They can be useful for reaching the precise backfocus distance as required by correctors. It features a knurled ring for easy gripping. Specifications Optical length 7. 5 to 100 mm Clear aperture 62 mm Outer diameter 76 mm Connection telescope side M68 x 1 male Connection camera side M68 x 1 female Weight 30 to 170 g