What kind of lens should I use to make a Galilean telescope an astronomical telescope will be better?
Wednesday, November 24th, 2010 at
11:52 pm
I like the Universe, but i have no telescope. They are not available in our area. So, i decided to make it on my own. Help me for galilean or astronomical telescope
What type of lens for objective and eyepiece?
 |
 Zoom Telescope Lens Rotatable Tripod for iPhone 4 4G  US $30.30
|
 CELESTRON C90 TELESCOPE 1000mm f11 LENS US $142.49
|
 8X Lens Optical Magnification Telescope for Cell Phones Cameras Black US $19.99
|
It is very hard to find suitable materials to make even a simple telescope. Telescopes are precision optical devices, and require skill and good materials. The best option anywhere in the world is the Galileoscope, which is available at modest cost (US$20) anywhere in the world by mail, though shipping will end up costing you more than the telescope itself. Heck I’m just a short distance away in Canada, and shipping was more than twice the cost of the telescope. Nonetheless, you will get excellent quality lenses of exactly the right size and type…I highly recommend this kit!
The second link is to a set of instructions for making a simple Galilean telescope. As you will see the lenses are more expensive than the whole Galileoscope kit, and must be sourced from various suppliers. These are small specialized optical houses, and you are inlikely to find local equivalents.
Good luck!
[Edit] I see the price of the Galileoscope has now gone up to US$49.95. This still represents a saving over buying individual lenses, since the optics are of better quality than the ones in the article. The Galileoscope has a 50mm glass achromatic objective and 4-element Plössl eyepiece, as opposed to the simple convex and concave lenses used in the Galilean scope. However, this also brings it to the same cost as the various 76mm reflectors on miniature Dobsonian mounts sold by Celestron, Orion, and SkyWatcher and now widely available all over the world.