Q: What’s the best colour tint for sunglass lenses?

A: The short answer is: choose brown to enhance your perception of pleasant colours like greens and reds, or choose grey to limit brightness without altering colour perception. There are other, equally important attributes to sunglasses. Lens materials can affect transparency and durability. Polarised lenses reduce glarish reflections from shiny surfaces like icy roads or sun on the water. Ultraviolet protection is necessary to prevent short and long term damage to the eyes. Photochromic tints get darker in brighter light and can increase the functionality of the lens. The size and shape of the lens is important for adequate coverage. An anti-reflective coating on the back surface of the lens can reduce reflections from behind the wearer. The general style of the sunglasses is important too, in that they should not be embarrassing to the point of not wearing them.