Magnification Specs?

Personally, I use a 7x loupe some times I'll go to a 10-12 power for varieties, a 20x only on my USB microscope. 20x is a lot of power for most coins, great for picking out doubling, or RPMM and RPDs, but for grading and general use 20x seems like overkill in power. My USB microscope is 20x or 200x I wish it was 2x-20x it would be a lot more useful to me for coins.

The one you link to shows no exit pupil size (usually in millimeters) 4-7 or greater would be ideal, I would bet these are very small, probably around 2.5-3mm in size for exit pupil. Larger is greater as we age our eys begin to shut down, making it harder to see in the dark. While exit pupil size is more important on telescope eyepieces, digital cameras and binoculars, it also applies to us with magnification. As we grow older we need more, and more light entering our pupil to help see details, through a larger magnifying glass or loupe you will get a large exit pupil which makes everything easier to see.

Relevant part from wikipedia article on magnifying follows:

Magnifying glasses typically have low magnifying power: 2×-6×, with the lower-power types being much more common. At higher magnifications, the image quality of a simple magnifying glass becomes poor due to optical aberrations, particularly spherical aberration. When more magnification or a better image is required, other types of hand magnifier are typically used. A Coddington magnifier provides higher magnification with improved beam quality. Even better images can be obtained with a multiple-lens magnifier, such as a Hastings triplet. High power magnifiers are sometimes mounted in a cylindrical or conical holder with no handle. This is called a loupe.
Such magnifiers can reach up to about 30×, and at these magnifications the aperture of the magnifier becomes very small and it must be placed very close to both the object and the eye. For more convenient use or for magnification beyond about 30×, one must instead use a microscope.
--end of article copy--

I use a Bauch & Lomb Hastings APO triplet 7x as my main loupe.

APO stands for apochromatic or color free (a good thing) not that it won't show color, just that it won't show false color, purple and yellow fringing you often see through cheap binoculars or camera lenses. When I sold telescopes we had a saying if you want that refractor telescope in apochromatic just add a 0 to the end of the price!

Stick with glass if possible something large enough to be comfortable in use, and one you don't have to jam into your eye to be able to use. I wouldn't buy any I couldn't try first or at least have a full refund on if they don't suit you and your needs.

too much magnification huh? That might be true...

Interesting. I have bought the small, handheld "microscopes" from China and have actually been happy with the quality of them for the price. Six dollars might be worth the gamble.

Here is one I have that I like a lot. Its 45X, which a lot of people say is too powerful, but I like to see the details and it definitely helps looking for RPMs etc.
[ebayitem]360503386025[/ebayitem]

Currently $1.98 free shipping - case and batteries included (I do use my case to keep mine in when in my pocket). So look around ebay if you are interested.

50 batteries 1.50:
[eBayItem]330542756096[/eBayItem]

Wow - last time I got them they were 50 for 1.00!

More ebay bucks just got me this for free the other day and I am finding I like it also - although I do not think it as sturdy as the first one mentioned here.
[ebayitem]170793264252[/ebayitem]

I would *think* a 5.00 loupe would be good based upon my experience with the various inexpensive things like the one posted above.



Let us know what you get and how it turns out.