Question about Bushnell NorthStar 78-8831 (525 x 76mm) Telescope

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Cannot see anything.

Just got a 78-8831 and set it up according to instructions.  After inserting lens into eyepiece, I can't see anything at all.  Dont worry, I've removed the front cap from the the main telescope.

Something leads to believe I'm either missing something real fundamental or my telescope is broken.  Please help

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Re: Cannot see anything.

Start by adjusting the focus draw tube all the way in, then back a little bit. In the day time indoors, remove the lens from the draw tube. Look into to the draw tube. You should be able to see your eye centered in the mirror. If you cannot see your eye at all, either the primary is tipped drastically or the secondary mirror is way out of adjustment. In that event I would return this scope to where you got it.

Posted on Nov 09, 2009

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When I use a Barlow lens do I insert it before focusing on an object through the eyepiece or do I insert the lens after I've focused on an object (eg: Jupiter)

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Your scope should have come with one or two eyepieces that are then inserted into the focuser. here is what an eyepiece looks like they come in 3 sizes, .965, 1.25, and 2 inch. MEASURE the hole in the focuser.

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Jan 22, 2010 | Bushnell Deep Space 78-9003 (525 x 76mm)...

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I dont know how to use my barlow lens

I use a barlow lens quite a bit with my telescope. It is usually inserted before the diagonal if you use one or before the eyepiece if you don't. The barlow lens for your telescope will double the power of the eyepiece used.

However, despite what the manufacturer claims for your telescope things will look quite poorly if you try to view at 180 power. Generally you'll get the best images by using 50x for each inch of your objective lens. For example, your telescope has a 50mm lens. That's roughly 2 inches. 2 inches times 50x gives you a maximum useful power of 100x. Depending on the viewing conditions you may be able to exceed this or not even reach it. Things will look blurry and dim when you try to use too much power.

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Bushnell 700x76

Just got a 78-8831 and set it up according to instructions. After inserting lens into eyepiece, I can't see anything at all. Dont worry, I've removed the front cap from the the main telescope.

Something leads to believe I'm either missing something real fundamental or my telescope is broken. Please help

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What lens do i insert into scope to view the moon

The moon is big so use the 25mm. The Barlow will have a multiplication marking on it 2x 3x etc. A 2x Barlow lens will effectively double the power of the eyepiece you are using. Do not use the erecting eyepiece for anything other than land viewing. Erecting eyepieces generally reduce the amount of light reaching your eye and thus reduce brightness of the faint objects in the sky.
So basically just place the 25 mm lens in the focuser and point the scope at the moon and you will be amazed at what you can see and how bright it is.

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If you dont have any experience with telescopes, I suggest trying it first in daytime, since daytime objects are much better for getting experience. Also, start with the lowest power eyepiece, the one with the largest lens. Start by looking towards something pretty big, like a car or a house, and it needs to be some distance away to even have a chance to get a focus. If your target is closer than about 1/4 mile, you should add the right angle eyepiece attachment to allow you to focus in on closer objects.

When you are finally set up with the low power eyepiece, and have a good big target in the daytime, start looking thru the telescope while turning the knob thru the entire range. At some point of knob turning, you should see some image appear in the eyepiece..Turn the knob slowly to focus it clearly.

And this is for the shaky tripod. If you can hang a book under the middle of the tripod, the added weight will help stabilize the telescope, and you should be able to see a little better, without so much motion at the slightest touch.

After you look at the first car or house, you can see how careful you have to be to use the telescope, and you can start to look at other objects. When you move to the higher power eyepieces, it will be even more critical in getting it both aimed and focused. If its off by just a few degrees, you wont see what you are looking for.

When you start nightime viewing, start with the largest object in the sky, the moon. Its the same process as daytime, except the eyepiece mechanism will have to be adjusted a little closer to the main body of the telescope.

Viewing planets and stars will be the ultimate test. Stars and planets are harder to see, since they are small, and hard to see unless they are in focus. When you can see those views, you have passed the telescope test. Its a matter of careful aim, and having the telescope focus set close to the point where you can see objects that are VERY FAR AWAY. If you are able to focus on the moon, you will be fairly close to being able to focus on the planets. The hardest part is actually getting the planet in the view of the telescope, in other words, aiming it.

The last item that can really mess up the view is a fogged up lens. Usually this happens in the summer when the scope has been in the air-conditioned room, and then it fogs up when taken outside. The solution for this is to let the telescope sit outside for 20 minutes, so the fogged lenses can clear. By the way, the same fogging may happen when you bring the telescope inside during the winter.

I hope this helps you eventually get a clear view of some amazing views in the sky. Your final exam is to take a look at the moon, the rings of Saturn, and the moons of Jupiter, some time in the near future. Have Fun!

Dec 26, 2007 | Bushnell NorthStar 78-8831 (525 x 76mm)...

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