New supplies and chemistry concerned inside the most current generations of the lenses have produced important development in addressing the two fundamental criteria for selection :
Older generations (and a few present generations) retain a yellow or somewhat jaundiced hue even if not exposed to ultra violet mild (indoors by way of example). The most recent technology Transitions are broadly regarded to become the top obtainable and virtually totally very clear in the absence of extremely violet.
Most more recent photochromatic lenses make a speedy transition from mild to dim as they're uncovered to extremely violet - the actual check as well as the differentiation will be the price at which they regress from the darkest tint to clear. Again Transitions lenses are widely thought to be best in class in this regard.
Transitions lenses really are a widely held trademark for any particular (latest) technology of materials and technology that are mixed and sold below the "Transitions" brand. Other (but equivalent) names usually are not the same, and therefore are generally regarded to become not as excellent, as they may be from older technology photochromatic technology.
Lastly - do not count on your photochromatic lenses (regardless of which brand or technology) to produce considerably of the distinction while driving, because the windscreen of the car is developed to soak up the majority of the UV before it enters the cabin - therefore the lenses within your eyeglasses have practically nothing to respond with. In the event you require or would like tinted lenses whilst driving, you might be much better off acquiring two pairs of the same frame with prescription very clear and prescription tinted lenses.