Hello,
All pretty simple (I think).
1. Is there an equivalency chart regarding lumens and candle power? I see that most manufacturers use lumens but some are still sticking to candle power. I assume that watts aren't a fair measure as other things such as bulb, reflectors, etc. come into play.
2. At what point (lumens) does a light go from "be seen" to "see"? I'm on roads and not mountain trails.
3. Since I don't carry a laptop and wouldn't want to carry around a recharger brick, can you suggest a good light that uses replaceable AA or AAA batteries? Can the rechargeable batteries in the USB lights use regular AA or AAA batteries while I tour? (Okay this is Q4 but it's related.)
Thank you.
Yes, if it's for road use, either the B&M Ixon Iq Premium (the premium part is important, the previous non-premium one was a lot dimmer). Or the Phillips Saferide. Depends on how much battery life you need - the Saferide is a little brighter and a nicer color temperature, but the battery life is slightly less than 2 hours. The Iq premium is 4-5 hours of battery life. Both take AA's. Both use a shaped beam that puts light evenly on the road where you need it, and so you can see well.
I own around $1500 in lights, and either of these are around $150 and I prefer them to any of my other lights.
It's very hard to get a pic that's truly representative of what the light looks like at night, but this pic illustrates the beam pattern:
Another - more expensive - option is a dynamo light. Same beam pattern, but powered by the front wheel turning rather than batteries. I use one on my winter bike and commuting bike, as it's much nicer to simply not have to worry about batteries at all. (Though it's definitely more expensive to get a dynamo light).