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Leo Lichtman Leo Lichtman is offline
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Default Got any eyeglass experts here?


"Gerry" wrote: (clip) Looking for something with a focal length of maybe
22" so I can stand at a comfortable position. Does that mean a stronger
lense?
^^^^^^^^^^^^^^^^
First. I believe your nomenclature is wrong. The focal length is not the
distance at which your eye focuses comfortably on the work. Lets drop that
term, and talk about diopters. A flat piece of glass has zero diopters,
and does nothing to improve your vision. If you go to a store that sells
cheap reading glasses, you will find an assortment of strengths, all
labelled in diopters. The higher the number, the closer you can focus.
Just try on different ones until you find a pair that makes you comfortable
at the 22" working distance you seem to like. They won't be safety glasses,
though. For that you will need to give some money to your optician.

I keep a pair around for removing splinters, etc, that are about 3 diopters.
Withg those I get a working distance of about 6-8" (guessing.)

I have another pair that are about 1.75 diopters that I wear under my
welding hood. It's really hard to line up tri-focals through a welding
hood. (Don't sneer. You'll be my age someday if you live long enough.)