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  1. #1
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    Lights during sunrise/sunset?

    Does it help to run my lights when the sun is at low angles such as during sunset and sunrise? Currently sunrise is just before 7am and I'm on the road as early as 745am.

    Part of my commute involves riding through wooded areas (Golden Gate Park) and I was wondering if it's useful to run my lights either in constant or blink modes on these roads. The lighting changes between sun and shadow repeatedly due the vegetation.

    I have a Portland Design Dangerzone rear and a Planet Bike front light. BTW, Portland Design claims 50 hours run time for the Dangerzone, but after only about 10 to 15 hours of use, I found that I had to charge my batteries with 370-390 mAH which is roughly half the capacity of the batteries. I conditioned the batteries twice each before I put them in my lights. The batteries are Sanyo Eneloops.

  2. #2
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    Does it help? Perhaps. Does it hurt? Not at all. Better to run the batteries down than to be run down yourself. Its one of those "if you had to ask, you probably should" things.
    Jason
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  3. #3
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    Also a concern I still have. Have given it some thought, time, and video. So here is a 'brain dump'. (You asked!)

    Riding away from a lowering or rising sun is different from riding into it being-seen-wise. Any light colored clothing especially the traffic green, orange, yellow, and yellow green, light yellow and white will reflect a lot of light back to drivers. You'd need a multiple 100's of lumens in a tail light to beat that. But as you say, you ride into shadows from buildings, trees, and terrain and the light clothing drops in visibility especially for eyes behind you still dealing with an excess of reflecting light. Then a tail light fills in nicely. I also think the effort to be seen registers with a lot of drivers and they seem to cut this cyclist a bit more slack.

    I find it strange that these safety devices, have few videos showing how well the products work in real situations at distances of 2 + seconds from them. What they look like up close in low light is NOT how they look in bright sun out on the road. I am hoping to purchase a video camera with more resolution and night capabilities that will document this better, but here is a video showing daytime bike lights and ANSI vest in a lowering sun (about 45 minutes to sundown) while riding away. It is a near worst case scenario and a real test for visibility. (The lack of resolution (720 x 480, not 1920 x 1080 of HD) means the camera doesn't see the flashing lights all the time at a distance unless they get a pixel or four, occasionally you see a flash at distance on the video that is quite visible to the eye. Though it would be lost in traffic, it would stand out if yours was the only light ahead.) It was posted in another thread , but i think warrants another posting here. The slant is because the cheap camera has no screen and it was made with a built-in slant I did not know about:



    The vest clearly outglows the lights. It is clearly visible on video at 1/4 mile. That is about the same as 1/2 mile with the human eye by my crude attempts to estimate the camera's nearsightedness. More lumens is better here in the close in range where there are enough pixels to compare. The ANSI vest is used by road construction crews so a motorist who claims they did not see it, is on some pretty thin ice, confession-wise.

    The 'Dangerzone' tail light is a double 0.5 watt LED light that looks a lot like the Princeton Tec Swerve. I have an example of the Swerve. It isn't a lot more noticeable than a Planet Bike Superflash. They are both about 12-13 lumens output. (I measured.) The PDW Radbot 1000 is about 25 lumens after is settles in (all have higher output on fresh cells for 15-60 minutes). The Radbot shows a marked decline in output with 1000 mAhr AAA's after 8 hours, the Swerve and Superflash tail off getting fainter and fainter as the cells discharge over more than 100 hours. The low cell voltage at some point, after say 20 hours, is is not good for the rechargeable cells and the low output isn't good for being seen. I recharge with my Radbots, but 16 hours would be my guess as a recharge time for 1000 mAhr cells.

    Riding into the lowering or rising sun puts reflective and bright clothing in shadow, and drivers' pupils contract behind polarized lenses (you hope). A glare of light off a car hood without polarized lenses essentialy blinds them for an instant and it won't matter how visible you are. I am planning on testing this sun orientation with video. My DIY 100 lumen tail lights are noticeably brighter than my cars LED brake lights, and brake ligths are visible in this situation (except for the case of glare and no polarized sunglasses). The question is whether 25 or even 13 lumen bike lights help much. They can't hurt. So run them. Just assume you are a more invisible than normal. Altering schedules to avoid these times of day gets complicated with DST and shifting seasons, but is a very viable way to increase your visibility.

    YMMV.

    Still haven't found what I'm looking for.

    Brian

  4. #4
    I Ride for Donuts
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    I use a blinky in the rear when it's like that...no front. My commute is rural two-lane road though... traffic is not a major concern. When I stop relying on the headlight and start looking way out ahead of it anyway, I use it for a couple more days and then ditch it.
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  5. #5
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    If I see marker lights on cars more than I see the car body, I kick myself for not having my blinker with me. Or turn it on, depending.

    I guess I'm mostly just repeating post #2.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  6. #6
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    I run front and back lights whenever I am riding on roads with traffic - day and night. The front light in particular (Dinotte amber daytime running light) has kept many a car from turning left in front of me, or pulling out of a driveway in front of me. Motorcycles are required to have lights on 24 x 7 for visibility, why not bicycles?

  7. #7
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    Since I still need my headlamp for the end of my commute home (almost 8p.m.), I use it in strobe mode in the a.m. - I like the reflection back to me off roadsigns, etc. But since I dislike being tethered to my pack by the cord, and would rather not have the weight of the light on my helmet or the battery in the pack, I will stop using it when the ride home is no longer dark. Woodway, is the amber front light distracting to you? I run the Dinotte taillight day & night, but don't know as I'd want to be looking at it the whole ride.

  8. #8
    I Ride for Donuts
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    ^^ I got a Planet Bike 2 watt Blaze headlight this year (upgrade for me, downgrade from the Dinotte)..it has a mighty powerful strobe mode, and it runs for a really long time on 2 AA's...no cords, no weight. Maybe a nice alternative in 'transitional light'?
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  9. #9
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    ^^ That might be a good idea, plus if I got stuck out after dark I wouldn't have to worry about it.

    While checking out the price etc., I saw this, which reminded me of Brian's DIY helmet swing mount blinky:
    Planet Bike Blinky 3H Helmet Mounted Self Leveling Rear Light
    Attached Images Attached Images  

  10. #10
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    I thought about this after I posted and thought why'd I even post. The cost of running the lights is minimal since I already bought them along with my NiMH batteries. Even at 20cents per kwh, an exaggerated electricity rate, the cost of running my light for one hour is only around 0.05 cents -- I'd have to run the light for 20 hours to use one cent of electricity.

    Just to see how bike lights looked during my commute, I rode about 1.5 mi east in the reverse commute direction on a MUP through Golden Gate Park after I got part way home. The MUP has many trees on either side and lighting changes repeatedly between shadow and direct sun.

    I passed 5 bicycles on the path coming towards me. The route is not popular amongst bicyclists because it's not obvious that it exists; one has to go looking for it. The first two were about 100-150 ft apart and using some kind of LED lights and I could discern them from the furthest away; the leader was running steady and the second bike was flashing. I could spot them as soon as they crested a hill from about about 2/3 mi away.

    Closely behind the two running lights was someone wearing a fluorescent green/yellow jacket and no lights. I had to get much closer to this guy, maybe 500-800ft before I was sure it was a bicyclist. I mean I could see something moving in the distance at about 1/3mi or so, but it didn't really register in my mind that I was looking at a bicyclist until he was much closer. I didn't know if it was someone standing/walking/running in the distance. Even then, from 1/2mi, I had to look for him among all the surroundings if I stopped tracking him visually.

    Bicyclist number four was wearing a teal jacket and black skirt and stockings. She was and not too different than the previous bicyclist with the yellow jacket. Just like the yellow jacket rider, I could see her in the distance but it was more the movement that initially caught my attention. The yellow jacket stood out more but the distances from which I could see them and have them register in my mind were about the same.

    Number five was also wearing a black SF Giants button up shirt with orange decorations and gray pants. He was just like the other two without lights but when he got within about 30-50 ft and happened to fall into shadow, I noticed that he had some kind flashing front light but it was much dimmer than than the first two. I'm not sure this was light doing him much good. It looked small, possibly something that runs on coin cells.
    Last edited by jseko; 04-05-2011 at 09:19 PM.

  11. #11
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    PB Blinky 3H: Disappointing.

    I have the Blinky 3H and the performance is disappointing. It's just not bright enough.



    Quote Originally Posted by mtbxplorer
    ^^ That might be a good idea, plus if I got stuck out after dark I wouldn't have to worry about it.

    While checking out the price etc., I saw this, which reminded me of Brian's DIY helmet swing mount blinky:
    Planet Bike Blinky 3H Helmet Mounted Self Leveling Rear Light

  12. #12
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    I wasn't thinking 2-way MUP and FRONT lights as Daytime Running Lights (DRLs).

    I am not surprised that a yellow jacket or jersey did not compare well to front lights flashing or steady if those are decent road lights (power and narrow beam). They are often 2-5 X as powerful into 1/2 to 1/4 as wide a beam as tail lights. It is harder to see the front of the vest because of the angle, and worse if I'm in the drops. So the sun reflection won't be nearly as good as if riding the opposite way.

    My front lights beat the ANSI vest handily, just as car headlights do. On flash, the head lights have days of runtime, and the dyno one runs as long as the 'energizer' in the saddle does. I get much better sharing of the road with DRLs as too many like to drive down the middle of the road and wait too long to get over. I have done all I can and more than the law requires. I am still invisble and ride as if I am.

    The Blinky 3H might be a way for those who don't think they're up to engineering their own helmet pendulum mount for a Radbot 1000 or two. I agree the 3H isn't enough power.

  13. #13
    I Ride for Donuts
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    My Bell Metro helmet has a strappy thingy on the back that I can clip my planet bike superflash onto when I jump on the 'other' bike with no seatpost mount. It's pretty convenient really. Got the helmet for something like $35 at Nashbar.

    You gotta go Superflash...I had another planet bike blinky taillight before, and it was laughable after seeing the Superflash.
    Attached Thumbnails Attached Thumbnails Lights during sunrise/sunset?-picture1.jpg  

    Lights during sunrise/sunset?-picture2.jpg  

    You have no excuse for driving to work
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  14. #14
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    If you like the Superflash circa 12 lumens (1 0.5 watt LED and two 1/4 watts), then the PDW Radbot 1000, circa 25 lumens (1 1 watt LED) gives you double the output which allows more effective daytime use. In fact, Planet Bike seems to think so too, with the Turbo model:

    http://ecom1.planetbike.com/3070.html

    This light looks to share the same back as the Superflash. If it does, it allows me to use the pivot mount I have as it is glued to a Superflash back. I wondered if they'd rise to the challenge of the Radbot 1000. I have no experience with it. I am expecting to place and order soon and will let you know. No reason to think it is much different than the Radbot 1000, though.

    I like the Superflash's crazy pattern - it is very attention getting, though the second flash option, the double -single flash on the Radbot is pretty decent. Remember, part of the proceeds of Planet Bike sales return to support cycling. I'd give it an 'to be confirmed in tests but should be excellent' endorsement.

  15. #15
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    I just received a 900 lumen headlight and I kind of regret it since it was an impulse buy. At the time, I didn't realize the light system is 900 grams. I haven't tried using it yet, and I'm not even sure how to event mount it on my bike or helmet. There are LED lighting system that output that much light and weigh about 2/3 as much and have about the same run time. Heck, I'm not even sure I need 900 lumens.

    I'm thinking of getting one of those Mininewts or similar that don't have separate light and battery instead.

    Not
    Last edited by jseko; 04-06-2011 at 10:13 PM.

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