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Re: Prescription sunglasses for astigmatism
" I have a fairly substantial astigmatism (-3.25 in each eye)"
At least in the US, astigmatism is measured by DEGREES, as in rotation of an axis. Your main visual correction is measured as a plus or minus diopter figure, and a -3.25 would mean you are somewhat nearsighted and probably can't see faces clearly at 25 feet. An rx of "-3.25 x 180" would indicate the same diopter required--but an astigmatic axis of 180 degrees. If your Rdx does not have the "x ###" after the diopter, you have not been given an astigmatic correction.
So are you absolutely SURE that rx is just for astigmatism??
That's got nothing to do with astigmatism, that's just called needing glasses.
There's no perfect solution, you simply need to TRY things and yes that will waste some money but that's the only way to find out what works for you. Sailing? Contact lenses can be great, they're nearly "air" these days and when fit properly, you can't feel them. There are limited options for correcting astigmatism on contacts though. Contact lenses also dont have any problem with salt spray or rain, you just use plain saline or lubricant drops if/as needed. OTOH sunglasses will get salt spray on them, and if you clean that off without fresh water and a clean cloth, you'll destroy plastic lenses pretty quickly. Glass lenses resist way better.
If you do get lenses made up for your Rx...sometimes you get what you pay for. Every year that "chains" are surveyed, they get rated for not getting accurate prescriptions compared to independent optometrist offices. And the independents often can match prices, if you just mention that you'd LIKE to do business with them, but the prices...
FWIW in the US lenses are only made to the nearest 1/4 (0.25) diopter, so a tolerance that is 1/8 off your exact rx is considered as good as it gets. The axis for the astigmatic correction depends not only on how the lenses are made--but also very much on how carfully they are fitted (rotated) in the frame. So there again, a fast chain shop often doesn't do it as well. I'm sure there are some that do--but the surveys say "not likely".
What do I wear? Sometimes contacts, sometimes glasses. On the longest brightest days? I'd rather wear contacts, because I've got some incredibly dark sunglasses I can use with them, that would mean too many pair$$ with an RX. And some that just can't bemade in an Rx at all, like gold-flashed glacier glasses, that block all IR and UV.
Last edited by hellosailor; 04-21-2012 at 04:33 PM.