New supplies and chemistry concerned in the most current generations from the lenses have produced considerable progress in addressing the two basic requirements for choice :
More mature generations (and some present generations) retain a yellow or slightly jaundiced hue even if not exposed to extremely violet mild (indoors by way of example). The most recent era Transitions are extensively regarded to become the best accessible and nearly completely very clear in the absence of ultra violet.
Most more recent photochromatic lenses create a speedy changeover from gentle to dim as they may be uncovered to ultra violet - the real check along with the differentiation would be the price at which they regress from the darkest tint to obvious. Again Transitions lenses are extensively thought to be ideal in school in this regard.
Transitions lenses certainly are a widely held trademark to get a specific (latest) generation of supplies and technologies which might be mixed and sold beneath the "Transitions" manufacturer. Other (but related) names usually are not the identical, and therefore are normally regarded to be not as good, as they are from more mature technology photochromatic technologies.
Lastly - don't count on your photochromatic lenses (regardless of which brand or technologies) to produce a lot of a difference while driving, because the windscreen of a car is developed to absorb the majority of the UV just before it enters the cabin - hence the lenses inside your eyeglasses have nothing to respond with. In the event you require or would like tinted lenses even though driving, you happen to be far better off receiving two pairs of the same frame with prescription obvious and prescription tinted lenses.