I forgot: the more powerful the magnifier, the closer you have to hold the work. If you leave the lenses on, you can end up waving glue bushes and soldering irons just beyond the end of your nose.
Did I mention that the magnifying lenses don't work with my reading glasses?
My dentist has a pair of glasses with binoculars in the middle of the lens. Must ask her where they come from.
So THAT is why I keep getting blisters on the end of my nose!sign1
That is the biggest reason for using a desk mount magnifier instead of the kind you can wear - it keeps a lens between you and the soldering iron!