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7/50 Magnification binoculare

We have misplaced our instructions. can you help me?

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Hold binos up to your and close to fit your eye span.......adjust left eye with center wheel ...then adjust right eye with right eyepiece

Posted on Aug 18, 2008


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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

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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

Whats the major problem with supergiants

They're big, heavy and awkward to use, and the image is over-magnified for the size of the objective giving less than ideal image quality and brightness. A general rule (especially if using for astronomy) is that the objective divided by the magnification should never be less than 5. With 20x80's it's a less than ideal 4 so you'll miss out on many fainter objects completely. They can be excellent for lunar observation though as the Moon is so bright.

The high magnification also makes them almost impossible to hand hold steadily enough unless a tripod (or monopod) is used, adding more bulk and awkwardness.

Sep 28, 2010 | Zhumell SuperGiant Astronomical Binocular

1 Answer

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...

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.

Aug 21, 2010 | Optics

2 Answers

Need a manual for tasco 56t sd don't know how to use it

Here is the manual:

This is a very small 50mm refractor telescope. The same aperture as a pair of 10x50mm binoculars, which would have been better for viewing sky objects. The maximum possible magnification is about 100 power (50 times aperture of 2 inches).

The field of view is very small you must be pointed directly at the sky object to see it. This is why we recommend a pair of binoculars as your first telescope. Binoculars have a wider field of view which makes finding things easier for the beginner.

Read my TIPS on my profile page, and read this:

Jun 11, 2010 | Tasco Specialty 56TN (200 x 50mm)...

1 Answer

I am trying to find out what is 6x20

Binoculars are often refered to as "N x NN" which typically refers to the magnification and the size in millimeters of the front lenses (called the "objective" lenses). 6x20 refers to 20mm front lenses (about 3/4 inch) with 6x magnification. These would be useful as opera glasses, or for spotting birds in a small backyard.

The "N x NN" designation doesn't say anything about the quality of the binoculars - just the physical size and magnification.

Oct 06, 2009 | HiStar 6x20 Sportbinox

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Is my bushnell insta vision 7x35 or 10x50- how do I tell ?

The first number is the magnification the second number is the size in millimeters of the objective (large lens) So if you measure the diameter of the front large lens that will give you the size. So a 10x50 means a magnifyng power of 10 and an objective of 50mm.
Now to find out the magnification if you don't know what it is. Measure the front lens. Then if you look through the eyepiece lens while holding it away from you you will see that there is in each a small circle of light. That it what is known as the exit pupil. It lines up with the pupil of your eyes when you have the binoculars pressed up against your eyes. Now measure the diameter of the exit pupil in millimeters. It will only be a small number.

To work out the magnification use this formula. Magnification = Objective size divided by the exit pupil.
So a 10x50 will look like this M = 50 divided by 5....therefore M =10 which is the magnification.

Both the 7x35 and 10x50 will have an exit pupil of 5mm. So if yours is one of these then all you need is the objective (large) lens size.

Aug 04, 2009 | Bushnell InstaVision Binocular Binocular

2 Answers

My Nikon Action 16 X 50--4.1 --serial number 715480BJ

id take thm back then the prisems may be out of line

Jan 29, 2008 | Nikon Action Binoculars

1 Answer

Double vision

The distance between the centers of the eyepieces of your binocular must be the same as the distance between your pupils. This distance is adjusted as follows: 1. Focus on a distant object. 2. Pivot the two halves of your binocular farther or closer apart until you can see a single unobstructed, circular field of view. Make sure to focus on a distant object when you do this because when you focus on a close object you always see two slightly overlapping circular fields. Your binocular may have a scale on the top, between the eyepieces, to help you remember this setting.

Jul 03, 2007 | Bushnell Powerview - Compact 10 x 25...

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