United Scientific LCV108 Glass Double Convex Lens, 100mm Diameter, 200mm Focal Length

This is the worst example of a biconvex lens I have ever come across. The optical aberrations in it are so glaringly obvious and severe that it cannot even be used as a simple magnifying glass. There is severe distortion at the centre of the lens - the worst place for it to be.What they also don’t tell you is this lens is made in INDIA, and not in the United States. It’s a shame, as the only other source for lenses like these is China, and you’re going to run into the same issues with lenses from there.