Originally Posted by
Ian Jordan
Visual responses in low illuminance are not as simple as just increasing lens transmission. It affects Rx (usually a myopic shift - although some people become hyperopic), magnocellular processing, contrast sensitivity and 3rd order aberrations.
These should ALL be addressed by optical professionals - sadly they are usually ignored.
As for tints - why yellow? I wear a specific (not quite yellow) tint for night driving ( together with a lens specification which takes into account all other effects) - the difference in acuity, contrast sensitivity, edge and movement detection is remarkable. "Starring" of headlights (a columnated light source) is eliminated, ability to see in the distance is enhanced and my safety is much greater.
Whilst the obvious answer is to increase transmission at night - it is often poor advice. In fact here in the UK it can be a criminal offence to drive with tinted glases. That leaves me in a profesional dilemma - to give people measurably better vision - or to comply with a law which can be shown to be wrong!
Oh - and I do have the instrumentation to test for these effects - so I can say with confidence that the effects are not imagined.
I am your honour guilty of wanting to see better!
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