Compensated Reading RX

[burke110]

Wondering what formula you use to alter reading rx based on reading material distance. Is there a standard formula out there? Thanks in advance.

[Barry Santini]

Any good formula would HAVE to know in advance at what distance the reading RX has been refracted at. In the absence of this, our industry assumes 40cm (16 inches). Using diopters let you add and subtract easily values easily, so calculate the dioptric difference for the ranges involved and add or subtract as necessary.

Barry

[Trip]

" so calculate the dioptric difference for the ranges involved and add or subtract as necessary" _ I don't know if Barry, or others could take a moment and illustrate an example of how this would work ...... I am likely over simplifying in my head and not getting predictable results.