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How to focus telescope lens for city viewing?

How to focus telescope lens for city viewing for model T-600? Which lens is best? Note: Loss user manual... Is there a download user manual available?

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No no manuals. The smaller the number written on the eyepiece the GREATER the magnification.

However many astronomical telescopes show everything upside down. This is normal -- no up or down in space. You can buy and erecting prism diagonal for terrestrial viewing which will turn the image right side up.

Posted on Jan 31, 2010

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I can not get the telescope to focus. The viewfinder will not focus in. and can't see anything out of the out of the optical tube.

This type of telescope is viewed from the small tube at the rear. Use the longest lens you have. Most people think that they need magnification, but that is not accurate. A 5 mm lens will only have 1/6th the field of view (how much sky you see) compared to a 30 mm. The picture below was taken through a 50 mm lens.

Dec 20, 2014 | Meade ETX-90EC (325 x 90mm) Telescope

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I have a makusutove 150 1800 telescope and I cant seem to get it to focus correctly - it seems as though the mirrors are focussing the light behind the viewing lens. I can get a focussed image if I hold...

You do not have enough BACK-FOCUS, you need an extension tube for the focuser like this one:

Buy the correct size for the focuser hole--

Jan 21, 2011 | Tasco 49114500 Spacestation(r) 114mm...

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I dontknow how to look through it andfocus on a star,or moon

Hi Joe, I'm Mark.
The small scope on top of your big scope is called the "finder" scope. Probably 2X or 4X. It should have cross hairs in the view. Find the moon with it. It will also require focusing but since the moon is bright, you can get an idea where it is in the lens by that.
Next. Find the LOWEST power eyepiece to insert into the lens holder. And rotate the focus knob.
Hopefully, you will see some bright blurry thing and then you can focus on it.
After you get it in focus, put on a more powerful lens and look at the craters on the moon.
Note: You will need to adjust your telescope to the earth's rotation. Your scope should have
instructions for accomplishing this.
Hope this helps,
Best, Mark

Dec 28, 2010 | Tasco 200x50mm Refractor Telescope

1 Answer

Hello there, my name is Paul and I had just recently purchased the Vivitar Refractor Telescope 60X/120X with Tripod. I have assembled everything correctly, however I have tried to view the moon, but I...

This is one of the worst telescopes you could have purchased. Plastic eyepieces and a plastic focuser! We receive many complaints about not being able to focus.

Try again--- next time buy one of these which is the best value in amateur astronomy.

Nov 14, 2010 | Vivitar (1607225) Telescope

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My lens adjuster broke on my telescope and I can no longer adjust my view. it seems that the wheel had plastic teeth. Where can I get a replacement and what is the real name of this part?

You can buy another FOCUSER at several online sites-- here is one:

Sep 08, 2010 | Meade Infinity 114EQ-DH Telescope

1 Answer

Can't focus using 5mm lens

TOO much magnification for that 3 inch telescope. The most you will get is about 120 power or so on perfect sky nights. Try a 10mm or 9 mm as your most powerful eyepiece.

50 times aperture is the maximum possible.

Jan 19, 2010 | Meade ETX-125EC (500 x 127mm) Telescope

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I am 9 can't see out of my galileo 700x60 telescope what do i need to do

there are 3 types of telescopes:
1)refractor, uses lenses
2)reflector, uses mirrors
3)catadioptric, uses both

try this and practice doing this during the day time, it's easier.

get your eyepiece, the one with the highest number on it (# mm); this is your lowest power eyepiece, always use this first (wider view and easier to see where you're pointing it), and place it in your telescope.

next, use the focusing knob to focus on a target (a faraway tree, lamp post, etc.). once you have it focused, and if you want to get a closer look, get the next highest number eyepiece and refocus on the target. this is how you change magnification.
if you have a barlow lens (2x or 3x) this will also change the magnification by 2x or 3x without having to buy other eyepieces, although you can still buy more.
put it together in this order:
eyepiece-->barlow lens-->telescope

use the star diagnal for land viewing.

if you have a reflector telescope,
the open part of the telescope tube next to the focuser points to your target. focus it the same as above.

oh, and sometimes, with refractors, you might have to use the
45 degree or 90 degree diagnal to focus the telescope.

and google how to use a telescope. there's nice observing tips :D

hope this helps :D

oh, and check out the moon at night. it's a very nice target.
best time to observe the moon is when it's not full.
you gotta check out the 'terminator' (area on the moon where the light and darkness is separated.

Aug 12, 2009 | Galileo 700 x 60 Refractor Telescope

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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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Hi there,
the image in your telescope is suposed to be upside down (you'll find it's back to front too!). The reason for this is to get as much light to the eye as possible, the more lenses/mirrors the light has to go through/reflect off, the greater the light loss, and in astronomy you need all the light you can get.
For terestrial viewing, you can purchase, quite cheeply, an image erecting adaptor. This will make your image the right way up. For the best terestrial viewing, you can still purchase prismatic adaptors. Best bet would be ebay.
If I can be of any further help, don't hesitate


Mar 11, 2008 | Meade TeleStar DS-2114ATSA Telescope

1 Answer

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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