The SD81S II OTA is an Apochromatic Refractor Telescope
It features high-performance Super ED Glass(SD) made of leading-edge FPL53 glass to deliver extremely clear and sharp images by eliminating color aberration. This SD glass is designed to gather all g-ray (purple), C-ray (red), F-ray (blue), d-ray (yellow), and e- ray (green) to about a "0" value, making excellent lens material which reduces chromatic aberration over all colors.
The light baffle positions in the drawtube are arranged to take advantage of the entire field of view of a DSLR camera with a full frame image sensor. When used in combination with the new optional SD Reducer HD Kit or SD Flattener HD Kit, you will have a 44 mm image circle with full-format DSLR cameras.
The Reducer DH, sold separately, includes the SD Flattener DH and is essential for wide field astrophotography with the SD Scopes.
Eyepieces are also sold separately.
- Coating :Multi Coating
- Finder Scope: Red Dot Finder
- Adapter Thread: 60 mm/ 42 mm for T-Ring
- Visual Back : 50.8 mm and 31.7 mm Push fit with the supplied flip mirror diagonal