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  #177  
Old March 17th 17, 07:23 PM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 4,018
Default More About Lights

On Thu, 16 Mar 2017 20:26:57 -0700 (PDT), jbeattie
wrote:

Not yet, but I'm not really talking about my headlight.
I'm responding to James' statement that a candle should
produce enough light to ride a bike at under 10kph.
-- Jay Beattie.


Nobody seemed to like my acetylene lantern alternative, so now we're
doing candles. Sigh.

One candlepower = 0.981 candelas = 12.57 lumens.
However, this is tricky because candlepower and candelas are a measure
of light at the source, not light at the object illuminated. This
might help (or add to the confusion):
http://www.theledlight.com/lumens.html

My eyesight is slowly deteriorating. When riding, I don't wear
corrective glasses. The result is that I can see fairly well past
about 7 meters, but anything closer is otto focus. Potholes are
usually closer, so all I see is a blur on the roadway. More light is
a big help, especially if there's a shadow available to highlight the
edge of the pothole. At night, potholes just merge into the road
debris. My solution is to avoid riding at night, or ride very slowly
and carefully.

I think these are for a bicycle but I'm not certain.
https://s-media-cache-ak0.pinimg.com/564x/b0/bf/b1/b0bfb19778bfa3f85b8849983bc0d2f3.jpg
https://s-media-cache-ak0.pinimg.com/236x/6e/23/fd/6e23fd668b4e57681b8bcbdff7ec71f6.jpg

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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