Measuring magnification

[hellogreen]

How to Measure magnification
How can I see how strong a magnifying glass is?

I hear a lot of people talk about
magnifying and how strong the magnification is, but I would like to know the true
magnification of my magnifying glass. I have a few of them and some seem stronger then
others. How can I rate these? How can I pin a correct number on mine? How do the companies
that make these come up with these numbers.

[kerwin kanago]

Magnifying glasses are usually a simple convex lens. The magnification depends on distance to your eye, distance to the object you're viewing and the Optic Power of the lens, which is rated in Diopters. A larger diopter rating will produce more magnification (but a cheap, small diameter "strong" lens might make a bad/distorted, though bigger, image).

Wikipedia (naturally) has a pretty good article on it. Here

[tedanderson]

Hmmmm.. so I guess you need to know this so that you can look at ants under the sunlight?