Quote Originally Posted by CCGREEN View Post
Barry

What is "a valid corneal reflex measurement'? We know what a reflex measurement is but what is a "valid" one? Then I have to ask you what makes it valid or non valid?
Sorry, just asking.
Optimensch intuited what I was after. WE all "assume" that a cornel reflex measurement represents where the eye is looking, i.e., the "visual axis." But there are studies out that show that this can be a flawed assumption.

What we really want is exactly where the wearer is looking, adjusted for the plane /VD of the fitted lenses, and encompassing as DV prismatic effects, if present.

At the present time, the ONLY way is to use the Feinbloom method, a completely subjective approach. Perhaps soon in the future, we will have instrumentation or even an app that could result in better and more representative measurement values.

B