GSO - 12" f/5 Dobsonian GSD 980

Join the growing mumber of happy users of GSO quality telescopes! The large 12" Dobsonian is a impressive telescope, not only due of his powerful mirror, it´s really large. The telescope is too large for the backseats of the most cars, so you need a station wagon because the tube has a length of 145cm.

At the night sky the GSD 980 shows an impressive performance. So you can observe every object of the NGC catalog. You can see so many objects in Virgo that you can observe many nights and you won´t see objects twice!

The centerpiece of any telescope is its optics. GSO produces parabolic primary mirrors of very high quality. It is our firm opinion that GSO offers better mirrors than typical in this price range. We guarantee a diffraction-limited performance, which essentially means that the performance is limited by observing conditions and the laws of physics rather than by the telescope itself!

On most Dobsonian telescopes the altitude bearing is a very simple design. GSO has developed an improved altitude bearing with additional functionality: A strong steel shaft bears the weight of the tube. The tube is guided and kept in position through two CNC machined surfaces. The desired tension can be freely adjusted with a large knurled knob on both sides. This is particularly helpful when changing eyepieces where the telescope is temporarily out of balance.

This is another major improvement of this bearing system. The telescope can be balanced by moving it up or down a couple of centimetres. This may be necessary when adding a second finderscope (e.g. a Telrad) or when using very heavy eyepieces or a binoviewer. A scale on both sides allows you to easily achieve a symmetric bearing position.

The new GSO Dobsonians have a modern industrial roller bearing for a very easy movement. Metal plates above and below the bearing prevent the rollers from sinking into the softer wood of the rocker box, so the movement will remain smooth even after years of use.

Characteristics:

• Parabolical main mirror - better, than diffraction limited
• 94% forced reflection
• Aperture 300mm, focal lenght 1.500mm, f/5.0
• 2" Crayford focuser - 1:10 micro - reduction, adapter from 2" to 1¼"
• Rigid metal tube for good mechanical stability
• Tube weight appr. 19.5kgs

Delivery:

• GSO Dobsonian 300/1500mm Telescope
• 2" Crayford focuser - 1:10 micro - reduction, adapter from 2" to 1¼"
• 2" Extension tube
• 30mm 2" Wide Angle ERFLE with 70° field for good overfiew
• 9mm Super Plössl 1¼" - multicoated
• Eyepiece and accessory tray for eyepieces and filters
• Collimation manual