rparedes said:
What are you guys wearing on real dark, cloudy days. All my glasses have lenses for sunny days but every time i ride on a dark day i can't see a thing!
I've looked on-line for some interchangeable lense glasses but it seems like a pain...
any brands/type you suggest?
On overcast days, what you want is something that will boost the apparent contrast in the scene, and yellow/amber coloured lenses fit that bill perfectly. Our retinae are programmed to respond to changes in contrast (i.e. dark/light areas), and the increase in apparent contrast with yellow lenses on an overcast day really is spectacular.
Don't use them when its *very* dark, though, since yellow lenses are still deisnged to cut out a fair chunk of light (something like 40-50% IIRC), and taking away light is worse than not seeing contrast.
If it's just plain dark (eg. dusk/dawn), then you're better off with clear or very lightly tinted lenses. Clear lenses lose between 1-8%, depending on the coating on the lens and you want as much light getting in as you can.
Your best bet may be to own two pairs of glasses. This is because most photochromic lenses (ones that change shade with changes in UV light) aren't useful for overcast days, because the level of ambient light may not be enough to darken them, and when they do, the shade that they darken to isn't ideally suited to overcast conditions.
I'm sure one of the more expensive manufacturers has overcome this, but haven't kept up with the market to know enough. Let us know if you find any one product that fits the bill.
HTH,
n