Quote:
Originally Posted by Troll2k
I am not sure.Have you seen the cost of designer frames lately?
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I used to work in an opticians.
A prescription is broken down into parts like this
Sph cyl axis prism add
Sphere is - or + optical diopter which come in increments of 0.25
The symbol + or - means you lenses are either concave or convex, longsighted or shortsighted...
Cylinder is due to the shape of the eye not being a perfect sphere and is where present always has an axis.
Prism is serious stuff, I dont think I need to explain. You will know if you have prism in your Rx and will definatley need Rx lenses.
add is addition, this is what the optician literally adds to your Rx (perscription) to make your standed glasses reading glasses...
If you have no prism, and little cylinder 0.25 or less and your sphere is fairly balanced equal on both sides by around 0.50 you dont need to buy intermedite specs from an optician... You could buy some ready readers of a weaker perscription than the combination of your sphere and add... Obviously, if you get any eyestrain or tired eyes you have either got the wrong strength and or you will want to see you optician and get some perscription glasses... Also the addition and shphere is worked out differently if you have a +cylinder, the perscription has to be transposed and it affects the outcome, I only worked in -cylinder... I do not know the formula.
I would get in front of your computer first and measure the difference then replicate that distance when sampling the ready readers in store...
I am not an optician - you do this off your own back. 