Don't be fooled by misleading magnification product descriptions that use the optical power number as the magnification strength because it sounds better. Here's how to quickly convert the optical power to magnification strength: Divide by 4 and add 1. For example, the 10 diopter magnifying glass in this set has a magnification of 3.5X (10 divided by 4 = 2.5 + 1 = 3.5X) which is very strong magnification. If a handheld magnifier had true 10X magnification it would be impractical to use. The glass would need to be extremely thick and curved and it would have an incredibly short focal range - less than an inch - which means that's how close you'd need to be to focus on your subject.
Trustpilot
4 days ago
2 months ago