On Sat, 21 Nov 2009 06:57:36 -0500, Wayne.B
wrote:

On Fri, 20 Nov 2009 20:28:16 -0800 (PST), Frogwatch
wrote:

My nesting dinghy that is supposed to sit on my sailboat foredeck was
an ugly shade of left over green paint and it needed repair.
So.........recalling times I have been in the fog and worried about
being run down in my white sailboat. I'll paint the dinghy the
brightest color possible.
I have now named her "Retina Burn". Fluorescent yellow/green on her
outside and fluorescent orange on the inside, it is impossible to not
see her. Unfortunately, I neglected whether the people around me in
the marina will object.

You're better off to buy a good radar reflector or two and hoist them
to the spreaders.

Heh - yeah but then you don't get to paint a dinghy with obnoxious
colors in a determined effort to render as many people blind as
possible. :)

Also here's a thought to consider with respect to the potential color
of the dignhy. Lime green and yellow (base lime green with yellow
trim or vice versa) is not as visible as you would think. The NFPA
did a study a few years ago about visibility of fire and rescue
vehicles and found that lime green/yellow were equal in terms of
potential accidents as red/white but when lime green was matched with
white, the accident potential dropped by almost 90%.

The reason is kind of interesting and something that I knew, but never
would have considered. The human eye is practically red blind at
night even under city driving conditions - in the darker country or
poor surburban lighitng conditions its practically invisible. While
you would think that the white would off set that disadvantage, it
turns out that the white actually enhances the color blending effect.

The lime green/yellow combination has basically the same effect but
for different reasons - the eye response to the combination confused
the eye and the brain does not process the information even with the
difference in spectrum - it's not a situation where the eye is blind
to the color rather that the two colors are so close in the visible
spectrum that the background effect is enhanced.

So if you were going to paint the dinghy for visibility, the better
choice would be lime green/white.

I was wondering about radar reflectivity a couple of days ago and
thought about this - I wonder if aluminized paint, non-fiber or fiber,
epoxy might be a way to paint a dignhy to make it visible to radar.

Or any small boat for that matter.

Might be worth testing out sometime. I can't find any relevant data
on the web about radar reflectivity of aluminum impregnated paints,
then again, I might not be using the right search terms.