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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 DSLR's, web cams and CCD cameras.
Please note we have had many enquiries about the use of coma correctors, here's a link to using the 8" Imaging Newtonian with the coma corrector. You can order the Altair Astro Photo-Visual Coma Corrector with this telescope at
a reduced price - just choose the option from the dropdown list below.
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. In fact, the high contrast design gives solar system webcam imaging and visual observing performance similar to SCTs with the same 35% central obstruction.
Altair 200mm F4 Imaging Newtonian features:
- 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.
- Light weight OTA - 8" of aperture weighing only 9.8kg (21.6 lbs).
- Tube length only 32”
- "No tools required" collimation knobs.
- 8 x 50mm finder scope 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.
Recommended accessories:
Unique baffling, a fast focal ratio, and a large aperture optimize this telescope for short exposure, high contrast, wide field deep space imaging. The tube is extended forward of the secondary mirror to cut out stray light for more contrast, and internal baffles run the full length of the tube. A side effect of the 15 metal baffles is an extremely rigid tube, with minimal tube-flex for long exposures compared to normal Newtonians. You can use a DSLR, web-cam, DSI-type camera, or CCD camera, with reduced Vignetting due to the enlarged secondary mirror. Excellent “webcam” imaging of the solar system is also possible as is visual observing with 1.25” or 2” eyepieces. Contrast levels are equal to (or better than) most Schmidt Cassegrain telescopes, due to the similar 35% central obstruction, matte black baffled internal tube, and the absence of a corrector plate to absorb and scatter light.
Above is an outstanding image of M33, the face-on spiral galaxy in Triangulum, taken by Craig & Tammy Temple in Tennessee taken with the Astro Tech version of this scope. The image was taken with a self-modified Canon DSLR. It combines 98 separate 240 second exposures taken over two consecutive nights. This image of M33 shows the kind of results dedicated astrophotographers can get with the 200mm Imaging Newtonian.
For more images please see Craig & Tammy temple's astro photography gallery: http://templec.zenfolio.com/p854189928
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.
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.
You can choose a coma corrector option in the menu below:
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