Question about scopes...

[Slater]

When looking at scopes, I always see numbers like 4 x 32. Now, I know I should know what this means, but... I don't... or at least I don't think I do.

Can someone enlighten me?

[Lynx]

scopes? what type of scopes? like are you talking hunting stuff?

[Slater]

yeah, like a rifle-mounted scope

[Lynx]

oh hahaha i thought you were talking about microscopes for a minute. i dont know anything about hunting scopes... but i know my microscopes, and the numbers on them tell you how small of a magnification you're seeing, maybe that means how far you can see?

[termyt]

From the website of Swift Optics:

WHAT DO THESE NUMBERS TELL US?
The first number tells us how much nearer objects will look when viewed through the binocular. An object (like a bird, ship, or race horse, for example) that is 500 feet away will appear 1/7 of that distance (71 feet) in a 7x glass, 1/8 that distance (62 feet) in a 8x glass, and 1/10 the distance (50 feet) in a 10x binocular.


The second number tells us first, how big the binocular is. A glass with 50mm (millimeter) or larger objective lenses will be fairly large and heavy, whereas a binocular with 21mm lenses will be small and compact.

These two numbers together tell us the light gathering power of the binocular. Divide the objective size (second number) by the magnification (first number) and you arrive at the Exit Pupil. This Exit Pupil is the small circle of light you see in the eyepiece when you hold the binocular at arms length toward a light source such as the sky or a light colored wall. The larger this exit pupil, the more light is getting through to your eyes, which is a desirable characteristic, especially in dim light.

The table below demonstrates that, the smaller the objective lenses, OR the higher the magnification, the LESS light is delivered to your eyes.

Binocular Exit Pupil
7x50 50/7=7mm
10x50 50/10=5mm
7x35 35/7=5mm
8x40 40/8=5mm
7x21 21/7=3mm
8x24 24/8=3mm
15x35 35/15=2 mm (approx)

It becomes apparent that magnification, or power, is not the only consideration when choosing a binocular. The light gathering capability must be considered as well. Another factor affecting the choice of power is that, the higher the magnification, the more noticeable the motion of the binocular becomes, because the binocular magnifies not only the subject, but movement as well. It is generally accepted that binoculars of 10x or higher magnification should be used on a tripod or other support to minimize the 'shakiness' of the image.

[Mithrandir]

I'd say termyt pretty much covered it all.

Which leads us to our second point. Don't ever shine a laser at a scope someone is looking through.

>.<

[Slater]

anyone else here looked at the sun through a pair of binocs?