Alan wrote regarding 'Re: [EE] LEDs as lighting' on Thu, Mar 02 at 04:03:
> >Wether the time difference is actualy reduces
> >accidents I don't know,
> 
> I have serious doubts that it does. After all a filament bulb is essentially
> instant on anyway, it must take all of 100 mS to reach full brightness, and
> fade again - apart from headlights that is where the fade of the glow is
> easily seen in the dark.

While the actual time difference is negligible, part of it is the
novelty factor for now.  When you see a light that goes from off to
full on instantly, rather than "fading in" like incandescents do, it
tends to grab your attention.  It's for this reason that I always
replace the 1157/2057 bulbs in my tail lights with 3496 krypton bulbs
when I get a new car.  They're as bright or brighter than a 3057 bulb
(which is itself brighter than the 2057 and 1157), but they draw less
power and the come on more quickly - somewhere between an LED and a
standard incandescent.  The price is a little higher, but anything
that makes it more likely for someone behind me to see my brake lights
(brighter and faster turn on) is a good idea, IMHO.

As an aside, any experienced drag racer will tell you that they can
see three stages in an incandescent staging light - the "just turning
on" stage, the "on but not full bright" stage, and the "full on"
stage.  Some have complained about using the LED lights, because it
screws up their launch strategy if they're launching based on anything
but the "just starting to turn on" stage.  I'm pretty sure most tracks
around here are still using the incandescent bulbs.

--Danny
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