| Features a very fast f/4 focal ratio 200mm optics (800mm focal length)
contrast-enhancing extended tube length with 15 internal baffles
oversize secondary mirror to cover a 35mm CCD frame
built-in cooling fan for faster primary mirror cool-down
2" dual-speed Crayford focuser with 2" & 1.25" compression ring
**Special Offer**
We Offer the Lakeside Motor Focuser at £240 when purchased with this telescope
light weight OTA - 8" of aperture weighing only 9.8kg (21.6 lbs)
"No tools required" collimation knobs
8 x 50mm finderscope in a quick-release bracket
dual mounting rings
silicon dioxide mirror coating for extreme durability
lower-than-glass expansion B270 mirrors free of internal stress
This 8" optical tube is a very fast focal ratio f/4 reflector that has been mechanically and optically designed for wide field deep space imaging. It can be used with 35mm cameras, DSLRs, web-cams, DSI-type cameras, and large format CCD cameras alike.
In addition to deep space imaging, the 8 inch Imaging Newtonian is also usable for solar system webcam imaging, as well as deep space and solar system visual observing.
Solar system visual contrast will be somewhat reduced compared to a longer focal ratio reflector because of the AT8IN’s larger secondary mirror that has been optimized for full-field photographic illumination. However, the visual performance will still be much more than acceptable - and if wide field viewing is your thing, look no further! The 800mm focal length makes it quite possible to achieve high powers for detailed lunar and planetary observing. A Barlow lens is recommended for crisp and sharply detailed views of the Moon and planets.
Extended optical tube with 15 internal baffles: To increase contrast, the optical tube is extended 8.75" forward of the focuser to keep ambient light from hitting the diagonal mirror. In addition 15 internal knife-edge baffles are installed down the interior length of the optical tube to eliminate any stray light that might get past the extended optical tube and lower the contrast. The baffles and tube interior are finished in matte black to further absorb stray light. The result is exceptional contrast, far better than a conventional reflector for both imaging and visual observing.
The 32" long x 9" diameter optical tube is fabricated of rolled steel, to allow the mirrors to cool to ambient temperature more quickly. While the rolled steel optical tube is a little heavier than a more-costly aluminum tube, the Sky & Telescope AT8I review points out that “it also helps make it a very rigid setup, which is a good thing for astrophotographers." The scope’s tube end rings are sturdy die-cast aluminum, to protect the tube during transport and provide exceptionally rigid support for the optics, “adding to the scope’s overall rigidity," according to the Sky & Telescope review.
2" dual-speed Crayford focuser: The drawtube has 34mm (1.35") of travel and there is 80mm of back focus available from the top of the focuser’s 2" accessory holder to the image plane. The focuser has two easy to grip coarse focusing knobs. One knob also has a smaller concentric knob with 10:1 ratio reduction for fine focusing. This provides precise focus control for CCD imaging. A drawtube tension knob on the side of the focuser lets you adjust the drag on the focuser drawtube to suit various equipment loads while focusing. A second knob lets you lock in a precise photographic focus.
Will require a Baader MPCC coma corrector for coma free imaging.
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