Loupe…doublet or triplet


can anyone explain the pros and cons for 10X doublet versus triplet loupes?

not sure which one i should order for my sister…


It is the number of lenses in the loupe, triplet is the best, no spherical aberration.


Hi Gary,

Ok, thank you!


Hi again,

for inspecting a diamond, would you recommend a 10X…or 20X…?


Diamonds are always graded using a10X. Many times, we will use a stronger power if looking for inclusions.


This is not exactly to your question, but possibly useful to know about.

I have 2 loupes, one very expensive, and both share the same issue of being very small and fiddly to use, at least for me. For inspecting detail of my work, not diamond grading, I like to use an old Agfa 8X photographer’s loupe because 8X is still pretty good, and it is much larger and less fiddly to use.

It surprised me that they are still made, astounded me with their price on Amazon, but they can be had in the $20 range on eBay.

At that price, handy to have around, just not as an equal replacement for a 10X triplet loupe.

By the way, it can be used either way, wider side toward the work, or black end (narrower) toward the work, which allows you to get in closer without the wide clear ‘bell’ end getting in the way.

Neil A


10x is the industry standard for inspecting diamonds, so to say a diamond is VS1 is to say the diamond is VS1 under a 10x lens.
The doublet and triplet loups differ by the number of lens. Three lens corrects the spherical abbreviation ( the out of focus areas around the outside of the lens) so a triplet will give you a larger "in focus " area to use. A coating is applied to the lens to
Cancel out cromatic abbreviation ( the rainbow effect appearing on the lens) to give a clear colorless viewing area.
Look for a Triplett Hasting loupe ( sometimes called “coated lens”) that addresses spherical and cromatic abbreviations.


Thank you all, very helpful!


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