I need reading glasses (+1.50) for close-up work and that's particularly inconvenient when skiing: gloves off, goggles off, glasses on, read the map, glasses off, goggles on, gloves on, realise I've forgotten what I've just read...
So I bought some "removable magnification lenses". They're D-shaped bits of soft plastic that stick onto the lower half of the lenses in ordinary glasses, to turn them into bifocals, sort of. I gather they're quite popular for diving masks, so that people can read their air gauges.
Generally speaking I'm very pleased with the result but the lenses do have a tendency to come unstuck. They're not really stuck on at all: you're supposed to wet them, press them onto the glass, and then let them dry out, so that they're kept in place by air pressure. This seems a bit optimistic, especially as skiing goggles are actually made of soft plastic, not glass.
So I'm looking for a better way to attach them - perhaps some sort of adhesive (I don't know which sort) applied very sparingly at the corners. Or transparent sticky tape? Any ideas?