Thread: Magnification

If 35x is sufficient, and you want to take snapshots or run video directly to your PC, how about one of these?

http://tinyurl.com/zscope

USB linked and easy to use, and since you use your monitor instead of the actual optics you may actually be able to see the edges even better. Or is my thinking way off on this subject?

It's the cheapest low-power USB scope I've seen. I don't own one, but it looks like it would work for edge viewing rather well.

Originally Posted by Rajagra

I've taken a risk and bought these:
30x +20x10x Jewelers Eye Loupes Magnifier for Jewellery - eBay (item 110377903212 end time Apr-19-09 11:30:00 PDT)

They seem identical to much more expensive items found at:
QUICKTEST Loupes from £20.00 upwards

They could be cheap knockoffs, but even the spelling mistake is the same, and at the price of 6 Euros they will probably be worth it either way.

Haha they arrived today. The quality is OK, but I was surprised when the 30X gave around the same magnification as the 10X!

So I used each one to focus an image of a distant lamp and measured the distance from the image to the front & back of the lens to work out the focal lengths. Using the formula Magnification=250mm/focal length I worked out the true magnifications.

Claimed magnification / Focus distance (to front&back of lens) / Calculated magnification range (i.e. range that could be considered honest.) / Calculated magnification using mid-point of lens to measure focal length.

10X / 19-35mm / 7.1-13.2X / 9.3X
20X / 15-28mm / 8.9-16.7X / 11.6X
30X / 24-39mm / 6.4-10.4X / 7.9X

So the 10X is honest, the 20X is stretching the truth, and the 30X is an outright lie. Pretty much what I expected on the whole, but I didn't expect the 30X to give lower magnification than the 10X!!!

Ouch. I did read something similar on amazon, which is why I stayed away from those cheapies.

I bought BelOmo instead. Couldn't be happier. Except my wallet is lighter...

Well for about $6.50 I'm happy. The quality is OK even if the magnification is not what they claim.

It just makes me wonder how many other people have bought "30X" loupes and really have 10X loupes without knowing it.

Originally Posted by Rajagra

Well for about $6.50 I'm happy. The quality is OK even if the magnification is not what they claim.

It just makes me wonder how many other people have bought "30X" loupes and really have 10X loupes without knowing it.

A lot.

When I hear on this forum "I use a 36x loupe" I think to myself...36mm.... Because I haven't seen a 36 power loupe. In fact, I haven't seen a 30 power loupe made by a well known manufacturer that wasn't hundreds of dollars and the viewing range so small, that it wasn't worth it. My 20x is hard enough to focus and the viewing diameter is rather small. I can't imagine how small a true 30x would have to be.

It looks like the BelOMO 20X loupe can be had
for about $30. Not bad! I have a cheap Chinese
($2.85 shipped!) on its way, if it is total junk
then I might have to grab something like the
BelOMO.

- Scott

Originally Posted by sebell

It looks like the BelOMO 20X loupe can be had
for about $30. Not bad! I have a cheap Chinese
($2.85 shipped!) on its way, if it is total junk
then I might have to grab something like the
BelOMO.

- Scott

I bought both the 10x and 20x BelOMO. I returned the 20x because it was impossible (for me) to really focus on anything. When I contacted the dealer and asked to return the 20x he said that if I had talked to him first he would have discouraged me from getting it as it is only useful for very limited applications.

I liked and kept the 10x.

I have a B&L 14x, a B&L 20x triplet and this 30x from Widget Supply.It isn't cheap but not too expensive and works fairly well. My old beat up B&L stereo scope in 30x is what I use the most though.