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Lesser viewing area in my telescope

I am trying to make a telescope on my own. It is showing good results also. But the viewing area that I am getting is very small. Even to read a small board I have to pan my telescope.

I have used a double convex lens of 1000mm focal length with 100mm diameter, and a double concave lens of 200mm focal length for eye-piece.
I have fixed these two in sliding tubes and that's all.

Please advise me what I should do in order to get a wider viewing angle.
Thanks and Regards

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Re: lesser viewing area in my telescope

All telescopes have small fields of view-- even what is called a "rich field scope" has only about 2 degrees of view. Most scopes only have about 1 degree of view.

The key component is a short tube and a fast mirror of F4.5 or faster.

Posted on Aug 04, 2011

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You have GOOD power? You can try and replace the hand controller cable--

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When i view object thru the telescope they appear upside down is that normal?

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.

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Why is the finderscope showing the view upsidedown?

All astronomical telescopes show upside down images-- it's normal. There is no up or down in space. You can buy an "erecting" prism for terrestrial viewing.

Read my TIPS on my profile page.

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Viewfinder views things backwards

Yes, most finder scopes show upside down images, it's completely normal.

This is an astronomical telescope. Even the main tube shows upside down images unless you use what is called an "erecting prism" for terrestrial viewing.

Jul 06, 2010 | Meade 70AZ-TR Telescope

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Why is my view upsidedown?

All astronomical telescopes show upside down views-- it's how they work. Nothing is wrong with your telescope. Read my Frequently Asked Questions TIP on my profile page.

Apr 03, 2010 | Bushnell 3" Reflector Telescope w/Talking...

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The view through my telescope is upside down. Why?

All astronomical telescopes show upside down images. There is no up or down in space.

You can buy an erecting prism from this supplier and others.

Astro-telescopes don't have this because it adds more glass between you and the sky object. These are only used for terrestrial viewing.

Nov 18, 2009 | Tasco Astronomical 302675 Telescope

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When viewing everything is upside down.

Yes, all astronomical telescopes show images upside down. There is no up or down in space.

Sep 01, 2009 | National Geographic 76AZ (525 x 76mm)...

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Cannot see anything out of main telescope

Do NOT use the barlow lens-- put the lowest magnification eyepiece into the scope-- practice focusing on the moon -- turn the focus knob slowly in and out until you get a sharp image.

Telescopes only show an area of sky about 1 degree wide or LESS--- this is about the size of the TIP of your finger held at arms length................ your scope is best used at low magnification.

Dec 30, 2008 | Edu-Science (10166) Telescope

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Telescope is only good for viewing!!!

your scope is 565mm focal length with a 60mm objective which makes it f:9.5. (telescope focal length divided by lens diameter)
all this means that the optics are capable of viewing larger planets. nebula is a bit of a stretch. maybe under exceptionally dark skies with at least 30min. of dark adaptation. brighter objects like m42 or m31 should be visible, bear in mind that only very large telescopes will resolve the slightest hint of color in nebulosity. the rest of us are reserved to gray scale. i would suggest using a 26mm eyepiece plossl if available. next make sure your finding system is aligned to the scope. this is best done during the day at a distant object like a radio tower. center the object in the eyepiece then align the finder.
next get your self a good sky map like stellarium software a freebie and a fav. to ensure your looking at what you think your looking at.

a word on eyepiece selection. magnification is calculated by dividing the focal length of the scope by the focal length of the eyepiece. for instance the scope is 565mm the recommended eyepiece is 26mm so the magnification would be around 22x.
a rule of thumb for optics is about 50x per inch of objective. which means your scope is good for about 100x. so by the math you would use a 5.6mm e.p. to achieve 100x, however as optical powers increase field of view decreases making it difficult to find objects. find your object with a wide field e.p. then switch to a higher power to zoom in. if the image gets fuzzy at high power attempt to refocus, if it doesn't clean up either your asking a bit to much from the scope or seeing conditions in the upper atmosphere may not be ideal. what ever you do don't give up there are some amazing things to see out there.

Nov 23, 2008 | Bushnell Voyager 78-9565 (120 x 60mm)...

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Cannot see an image through the lens

I bought one of these telescopes, and had trouble at first, but finally got some decent results. 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 12mm 50x, 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 start to 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 100x eyepiece, 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!

Nov 14, 2007 | Vivitar (1607225) Telescope

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