Viewing Coins Better?

I use my Belomo triplet 10X loupe, as it folds up easily & takes little space in my pocket. .

Lighted loupes / magnifiers are wonderful.

Fortunately, although I am in my late 70's, I don't use glasses.

My eyes are reasonably balanced, so for coin grading, I use
4X reading glasses, which have the big advantage of binocular vision; they have exactly the same prescription for both lenses.
Also use a 10X jeweler's loupe, which is the standard power used by the TPG's.

For really close up work, a 20x hand held gem examination three element lens which is normally used for examining internal flaws in cut gemstones. Hard to use 20x lens without experience, due to a very narrow depth of field.

Point source lighting is helpful, as opposed to general floodlighting.