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I have a Barska telescope. Model: 60800. Diam: 60mm Focal length: 800 mm. I think I put it together correctly, but I can not see anything through it... just black. Yes, I have taken the cap off the end. I am not sure what the best lens or eyepiece to use is and I am not sure how to focus it... Help please.

Posted by Anonymous on

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The power of the scope will be the focal length of the main objective (yours is 800mm) divided by the focal length of the eyepiece, so a 9mm eyepiece will give a higher magnification (and be dimmer and harder to focus and find objects) than a 20mm eyepiece. It is usual to have two or three different focal length eyepieces for viewing different objects.

Starting out, you want to use the lowest power, so the highest number, eyepiece. Do NOT use the Barlow lens if one came with the scope. Try it out during the day (but never point a telescope anywhere near the Sun). This will make it easier to find the focus point. There is a very wide range of movement in the focus mechanism, because different eyepieces focus at different points, but the actual focus range for any eyepiece will be a small part of the overall range afforded by the focusing mount.

It is unlikely that the finder scope will be much use in pointing the telescope until you adjust it to precisely line up with the main scope. Most manuals recommend that you do this in daylight, by pointing the scope at an object on the horizon and adjusting the finder to match. Once you have a tree or mountain peak in the center of the main scopes image, you can then adjust the screws around the finder scope to get the crosshairs centered on the same object. It is very difficult to do this job in the dark, especially as objects in the sky are constantly on the move.

Remember that astronomical telescopes usually show an upside down image. There is a good reason for this- erecting the image needs more bits of glass in the light path, which reduces the amount of light and increases aberrations. Even if this is only slight, astronomers prefer to avoid it, and they don't really care which way up the Moon or Jupiter appear. It is possible to fit an erecting prism or eyepiece to most astronomical telescopes, and some of them come with one.

Posted on Dec 31, 2010

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Does it make a difference to your viewing if you have a bigger length telescope or a smaller one


Focal length not physical length would better answer your question. Shorter focal length scopes have a lower power but wider view per size of eyepiece.
BUT!
Tasco telescopes are basically junk telescopes. Any telescope from Celestron, Meade, Orion, Explore Scientific or Televue (to name the more popular) will give you a superior view compared to the Tasco.
A 60mm scope has the maximum magnification of 225x (under perfect sky conditions. I suggest a small, short tube reflector in the 4 inch range. They are lightweight, have much more light gathering power (more important than magnification) and easy to set up.

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I need to purchase the meade polaris model # 60az-d eye pieces that you use to look through the telescope.


You need to purchase .965 diameter eyepieces. 700mm ( focal length of scope)/ eyepiece focal length=magnification. Maximum power of a 60mm scope is about 225x (under perfect conditions)
I would get a 25mm 700/25=28x for low power see link below
http://cgi.ebay.com/Meade-MA25-25mm-965-telescope-eyepiece-NEW-/230542978572?pt=LH_DefaultDomain_0&hash=item35ad6eae0c
and then for higher power 700/8=87.5x
http://cgi.ebay.com/Astro-Optics-8mm-Deluxe-965-Telescope-Eyepiece-/230543763551?pt=LH_DefaultDomain_0&hash=item35ad7aa85f
There are not many options with .965 eyepieces I would get a .965 to 1.25 adapter or .965 to 1.25 hybrid diagonal. That way you have more options on better eyepieces and the 1.25 eyepieces can be used for better telescopes in the future.

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I am wondering how good you should be able to see images through a bushnell skytour 78-9960 telescope i can see the moon good but all the planets are really small and cant tell them from stars really. i...


No -- just remember that your scope is only 60mm wide. This is almost the same size lens as a pair of 10x50mm binoculars. About the most usable magnification for any telescope is 50 times aperture. So your scope is probably around 120 power. Yes I know the box said 500 power or 675 power or some number that you can never achieve in that size telescope.

All objects in the sky are very small because they are very far away. It does not look like the PHOTOS taken by the Hubble Space telescope.

Read my tips on my profile page.

Clear Skies- and read these:

http://www.texasastro.org/telescope.php

http://www.texasastro.org/mounts.php

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BUSHNELL DEEP SPACE SERIES 420 X 60 REFRACTOR TELESCOPE MODEL 78


Do not buy either telescope-- both are junk.

Instead buy one of these --

http://www.telescope.com/control/product/~category_id=dobsonians/~pcategory=telescopes/~product_id=09804

http://www.telescope.com/control/product/~category_id=dobsonians/~pcategory=telescopes/~product_id=08942

http://www.telescope.com/control/product/~category_id=refractors/~pcategory=telescopes/~product_id=09794

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Barska information


Barska is one of the many brands stamped on Asian made optics. Many of the models they sold were sold by Celestron and others. Go to the Celestron web sit and poke around in the download archives.for manuals and I'm sure you can find a manual that covers a model similar to your Barska. Start with the FirstScope series.

Their is a lot of excellent astronomy freeware available, just google for it.
Geo.

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1 Answer

Lense, objective


Here's the link to the manual if you need it; http://www.tasco.com/products/manuals/specialty_30076150.pdf call; 1-800-423-3537 and they will be able to tell you how to get a replacement OL Hope this helps :)

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