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→Contacts: Cautions about 3rd party sources
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* Since it's easiest to get contacts at full prescription, and many people want contacts for outdoor activity, most people use prescription contacts and [[plus lenses]] over. This may put you in the range to use cheap drug store readers, but it's better to get good ones from a custom [[lens seller]]. | * Since it's easiest to get contacts at full prescription, and many people want contacts for outdoor activity, most people use prescription contacts and [[plus lenses]] over. This may put you in the range to use cheap drug store readers, but it's better to get good ones from a custom [[lens seller]]. | ||
* The next most common strategy is to use differential contacts with [[minus lenses]] over for [[normalized]]. This has the advantage of less total lens over the eye, and a thinner contact may be more comfortable and allow more oxygen through to the surface of the eye. (And in specific cases may affect the cost of contact lenses, when stepping down from the extended range brand to the normal range brand in the same material/design.) This has the disadvantage of requiring glasses for outdoor activity. | * The next most common strategy is to use differential contacts with [[minus lenses]] over for [[normalized]]. This has the advantage of less total lens over the eye, and a thinner contact may be more comfortable and allow more oxygen through to the surface of the eye. (And in specific cases may affect the cost of contact lenses, when stepping down from the extended range brand to the normal range brand in the same material/design.) This has the disadvantage of requiring glasses for outdoor activity. | ||
====Cautions about 3rd party sources==== | |||
If you buy glasses online, you can pretty much get optically clear glass and an anti reflective coating in any of the cheap brands. When wearing contacts, oxygen permeability and the fit of the lens to your eye surface are important to eyeball health. Whenever possible, get contacts fitted by a professional [[optometrist]]. If you get any contacts other than those you are fitted for, you introduce significant additional risks on top of the expected contacts risks. You can get contacts in the same brand, material, diameter, and base curve as your professionally fitted ones, but event the difference in thickness could affect fit. A bad fit may not be obvious to the wearer, but can cause damage to the cornea over time.<ref>https://coopervision.com/sites/coopervision.com/files/pfg0001_revg_biofinity_family_pfg_clean_sep2019.pdf</ref> | |||
==See Also== | ==See Also== | ||