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I have a VT-50 telescope. When using the 3*Barlow magnification the items i want to see (moon) are still fuzzy. Is this normal? Also, do I use the Barlow with the other power eyepieces? from Glen, hope you have the solution THANKYOU

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This is a 50mm aperture telescope. The same lens size as a pair of 10x50mm binoculars- slightly more than 1.5 inches.

The maximum magnification of ANY telescope is 50 times aperture, so your scope is about 75 power. The BARLOW is actually useless in this size telescope; it applies too much power. Yes I know the box probably said 250 power but it was a LIE!

Never buy another telescope at CostCo, or Wal Mart, or at a garage sale, or from craigslist unless you know exactly what you are buying.

Put the eyepiece with the LARGEST number written on it into the telescope, DO NOT USE the barlow.

Read my TIPS on my profile page.

Posted on Aug 22, 2010

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About my tasco 46-060675 D=60mm F=900mm come with 3 eye lense 1(sr4mm) 2 (k10MM) 3(k25MM) and two tube 1(1.5x erecting eyepiece) 2 (3xbarlow lense


The different eyepieces are to give different magnifications. This is worked out by dividing the focal length of the telescope, f = 900, by that of the EP. So the 25 mm Kellner (that is the type of optics in the EP) will give 900 / 25 = 36 times magnification.

The erecting eyepiece is used for terrestrial viewing. Normally with an astro telescope everything is upside down as that does not matter when looking at a star. So when you want to look through someone's bedroom window you use this.

A Barlow lens is an add-on magnifier. If you add this onto any EP (it normally fits between the EP and the scope) it will increase magnification x 3.

There is a practical limit to what any scope will deliver, governed by its aperture (the size of the front lens) and for your scope this will be about x 120 magnification. Beyond that the image becomes too dim and fuzzy. This means that your 4 mm eyepiece ( x 225 magnification) won't be much use. It will be hard to find the object you are trying to observe, it will be hard to focus, and the image will wobble around. Nor is your barlow lens much use either I fear.

You might consider another eyepiece around 18 mm to give a nice spread. A Plossl type is good. If you get serious about astronomy, I think you will immediately want a better scope after using the Tasco.

Mar 23, 2015 | Tasco Optics

1 Answer

What do you use the barlow lesns for?


The Barlow lens goes between the diagonal and an eyepiece. It doubles (2x) the magnification of the eyepiece used.It does this by halving the f/ ratio of the scope.
Eyepiece alone gives 35x; barlow with eyepiece =70x.

Note: this scope comes with an erecting eyepiece and is NOT suitable for atronomy use (other than perhaps the moon)

Mar 19, 2011 | Tasco Specialty 301051N (100 x 50mm)...

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No matter what lense I apply to the telescope (omega refractor 200x) I can't get a good view of the moon. What should I do?


Put the eyepiece with the largest number written on it into the scope. DO NOT USE the 2x barlow if you have one.

This is a very small telescope not much bigger in aperture than a pair of 10x50mm binoculars. You should be able to get enough magnification to see craters on the moon.

It will NOT do 200x power this is a lie that they advertise on low cost telescopes. The MAXIMUM possible magnification for any telescope is 40-50 times aperture. You scope is about 2 inches so 80-100 power is the MAX!. The sky conditions must be perfect to reach the maximum.

Never buy a telescope that advertises magnification on the outside of the box. Aperture and quality optics are much more important than magnification.

Read my TIPS on my profile page.

Dec 21, 2010 | Omega Refractor Telescope - 200x

1 Answer

Can not focus on full moon,erecting tube ,,barlow ????


Do not use the 2xbarlow, put the eyepiece with the largest number written on it into the focuser --- this scope is 50mm the same aperture as a 10x30mm pair of binoculars.

The max magnification is about 50 times aperture. Your scope is about 1.5 inches== so 75 power is TOPS for this scope.

Oct 24, 2010 | Tasco 200x50mm Refractor Telescope

1 Answer

What is the barlow lens for and how do i use it


It multiplies the normal magnification of the eyepiece. They come in 2x, 3x, 4x, and 5x powers.

Normally in a very small telescope like your scope, they are completely useless! They generate too much magnification for that small aperture.

You would normally put the barlow into the telescope, and then put the eyepiece into the barlow lens.

Jun 15, 2010 | Edu-Science (10166) Telescope

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What level magnification do I use to see jupiter or saturn in a telescope?


Your 3.5 inch telescope has a maximum magnification of about 170 power.

This is under perfect sky conditions and a perfectly collimated telescope. Galileo used 30 power magnification to see Saturn's rings and the moons of Jupiter!

Put the eyepiece with the largest number written on it into the focuser do not use the 2x barlow if you have one.

Point it at Saturn. You will see the rings. However they are almost slanted directly toward Earth right now. You will only see a thin line going across the planet.

By the end of 2010 they should open up again enough to make out the "ring" shape.

You only need about 50-70 power to view Jupiter or Saturn, or Venus. Mars is smaller and about 100 power to 120 power should permit you to see the disk of the planet (but it's still very small in the eyepiece).

Dec 29, 2009 | Celestron PowerSeeker 114 EQ Telescope

1 Answer

How I know the red dot is working ok, is


This is a 60mm telescope not much bigger than a 10x50mm pair of binoculars. Your maximum magnification will be about 100 power. Yes I know they said 200-300 power on the box. This was a lie.

Do not use the 2x barlow. Probably be just too much magnification. Put the eyepiece with the largest number written on it into the telescope; then try the same eyepiece with the 1.5x barlow. That is probably all the magnification the scope can handle.

Stars are always pinpoint light sources, no matter how large the telescope. They are hundreds or thousands of light years away.

The "red dot" should be pointed at exactly the same spot as what is in the eyepiece. Center a bright star in the eyepiece, then without moving the telescope... center the red dot on the star. Now you can use the red dot to POINT the telescope exactly to a sky object.

This web site may also help you:
http://www.cloudynights.com/item.php?item_id=810

Dec 28, 2009 | Konustart 700 (120 x 60mm) Telescope

1 Answer

I don't know how to work my telescope I don't understand what the 3x barlow goes and what it is for I cant' see anything I tried to set up the crosshairs with the lens but can't figure it out and I have no...


It multiplies the normal magnification of each eyepiece THREE times! In your small telescope you will probably never be able to use it. Magnification is the least important quality of a telescope.

Use the eyepiece with the largest number written on it, which is your LOWEST magnification. Practice focusing on a distant object during the day time. At night the moon should be your first target.

Nov 11, 2009 | Meade NG-70 (140 x 70mm) Telescope

1 Answer

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

1 Answer

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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