Author Topic: Snellen vs cm improvement  (Read 858 times)

Offline Robin mn

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Snellen vs cm improvement
« on: June 30, 2015, 04:00:40 AM »
Hi everyone
For the past two reductions in my normalized(distance) prescription have been made based on my snellen results.This is because apart from the initial 4-5 months of cm improvement improvements tend to occur in my snellen only.I started at 25cm -4D fullprescription dec2013
        cm improved to about 32-33 cm in the first few months.
         Now at 20/30 on -2.5D
I reduce my prescription after Snellen reaches 20/16.
My questions are:
1.Why does my snellen improve  without cm improving?My cm should havebeen  at least near 40cm.Is it because i don't use a closeup differntial prescription but naked eyes?
2.From where should I take cm readings: after pushing focus or without?
any tips for cm improvement.???
« Last Edit: July 01, 2015, 08:35:07 AM by Robin mn »

Offline Alex_Myopic

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Re: Snellen vs cm improvement
« Reply #1 on: July 01, 2015, 10:34:18 AM »
I think one of the two methods is more accurate when you have low myopia. For me I always use the Snellen chart at 6m. Why check my eyes at shorter distance while accommodating?

Offline Robin mn

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Re: Snellen vs cm improvement
« Reply #2 on: July 01, 2015, 08:39:05 PM »
I have found that I may have much more potential for cm after pushing focus but I'm struggling to fuse close up double vision.It takes much effort to push and then clear double at closeup than at distance.Then I may get to maybe37cm.Also the fact that my right eye is weaker adds to the problem.
i most often do not push my limits at closeup compared to distance as the closeup work involves doing things fast ecept for may be browsing the internet.
« Last Edit: July 01, 2015, 08:41:32 PM by Robin mn »