OPT 8" f/9 Planetary Dobsonian Telescope
We started with the most important part of any telescope...the optics. Our diffraction-limited 8" f/9 primary mirror is made in the USA of Pyrex, and is multi-coated for bright, sharp images of the planets, the Moon, and deep-sky objects. The mirror is center-marked.
The secondary mirror is small, with a mere 15.6% obstruction, to increase the contrast, and the spider is curved to eliminate diffraction spikes on bright stars and planets. The tube assembly is made up of two thermally stable Sonotube sections (upper and lower), and they are held in place with four truss poles. A truss tube carry bag is included with your OPT Planet Pro Dobsonian, and so is a light shroud and dust caps.
The Dobsonian base is made of Baltic Birch, and comes with real Ebony Star and Teflon bearings for smooth motions across the sky. The telescope comes with adjustable side bearings to allow the balancing of heavy eyepieces.
The focuser is a 2", two-speed Crayford-style model with compression ring fittings, and comes with a 1.25" adapter. Other accessories include a Telrad finder, 2" 30mm SuperView eyepiece, and as mentioned earlier, dust caps, light shroud, and truss carry bag.
OPT 8" f/9 Planetary Dobsonian Telescope Specifications...
- Tube Diameter is 9.5"
- Tube Length in Travel Mode - 40.25"
- Tube Length in Observing Mode - 76"
- Tube assembly weight is 31 pounds
- Mount Weight - 21 Pounds
- Dimensions - 28.25 x 22 x 16 inches
|Telescope Series||Discovery PDHQ|
|Optical Design||Newtonian Reflector - Open Truss|
|Mount Type||Dobsonian Cradle|
|Warranty||1 Year Warranty|
|Telescope Focal Length||1828mm|
|Telescope Focal Ratio||f/9|
|Limiting Stellar Magnitude||14|
|Tube Color or Finish||OPT Deep Ocean|
|Eyepiece(s) Included||30mm SuperView|
|Optical Tube Weight||31 lbs.|
|Total Telescope Weight||52 lbs.|
|Length of Optical Tube||76"|
- OPT 8" f/9 Planetary Dobsonian Telescope
- 2" 2-speed Crayford Focuser
- 1.25" Adapter
- 30mm SuperView Eyepiece
- Dust Caps
- Truss Carry Bag
- Light Shroud
- Heres a superior reflector... Review by Pete
1= Houston, We Have a Problem & 5= It's Out of This World
Heres what the ad doesnt mention but you'll find out...
The smaller secondary under16% produces such clean contrasty stars by putting less light in the diffraction rings that you WILL see fainter stars than a compareble aperture at F/4 or f/5.
Detail on Jupiters face in the best seeing is an overload of contrasts with swirling patterns of belts, eddies, festoons, spots and so on being so overwhelming you cant draw it.
Im an artist - no you cant draw that much detail accurately and fast enough before it all shifts. On averege nights the advantage is still there, but on great nights, literally, you will be speechless.
Saturns Titan reveals as a disc.
Doublestars beyond the Dawes Limit are clearly made out. Elongated doubles of differing magnitudes are seen breathtakingly.
Fine planetary nebula benefit from the high contrast at high magnifications revealing disc-like forms easier than faster systems when the sizes approach 5. Central stars show fantasticaly, again, due to the very high contrast diffraction patterns.
Lunar mountain ranges bristle with details so rich it can be difficult to seperate one peak from another as the overwhelming sight comes at you in one riveting texture of impossibly tight points of light and dark. You cant describe it and Ive never seen it imaged.
Globular clusters are especially suited to the F/9 due to again, high contrast diffraction patterns putting more light in the spurioys disc than the surrounding rings. As a result the wealth of stellar richness seen in these objects bely the apertures size. The needle spiked points of light in dense richness of chains, sheets and dazzeling cores is tremendous. Open Clusters can be just as moving. Even obscure NGC open clusters you may never have heard about suddenly dazzle with the perfection of the finestly gleaming points of light, you keep increasing the magnification to even believe it.
This scoe will redefine what you thought was possible with an 8 aperture. (Posted on 1/7/12)