Search:

Thanks again. I had got the entire thought process incorrect. I was trying to use basic Pythagoras' theorem to work out the power much like you would with compounding prism.

Have the equation...

"the person" thats me!! was sitting front of page with a triangle trying to remember if adjacent over hypotenuse or opposite over hyptonuse was sin or cos!! This is difficult for us mere optoms. All...

Thanks!

It has been a while since I have done this stuff, but I am writing some exams on dispensing and have forgotten some basic trig.
When resolving oblique astig into vertical and horizontal components...