Author Topic: How much to undercorrect for 20/40...ect  (Read 734 times)

Offline wtfgod

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How much to undercorrect for 20/40...ect
« on: May 19, 2015, 01:51:16 PM »
Currently working with -4(20/20) left and -10.25(20/30) right, how much would I undercorrect equally to get to 20/40? 20/60? Ect...


Also, what is the correction/distance connection? For example, you should use 20/20 to see something at 20 feet, 20/40 to see something at 10 feet, 20/80 to see something at 5 feet, or something to that effect.
« Last Edit: May 19, 2015, 01:58:43 PM by wtfgod »

Offline Alex_Myopic

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Re: How much to undercorrect for 20/40...ect
« Reply #1 on: May 20, 2015, 04:16:29 AM »
Your refractive state of each eye plus the diopters ftom the conversion Snellen to diopters given for example by Mr Otis' reply
http://www.iblindness.org/forum/relationship-snellen-to-diopters