hUGH tURNBULL WROTE:
>
>Half the dimensions (width and height) is a quarter the light. A half moon is
>only half the dimension in one direction, so half the light.
This is correct. The lumens depends on the surface area. What Foxy is
thinking of below is the inverse square law which defines how light
level falls off with **distance**.
I don't recall whose post is below about photographing, but:
* if you're going to photograph the moon itself, you'll use the same
basic exposure (sunny F/16 - I find ~1/2 stop more is better) no matter
what the phase of the moon, if you want some detail in the lit portion.
Cuase the EV level of any point on the lit portion of the moon is
basically the same. If you give more exposure ,the lit portion will
burn out rapidly, but you will begin to see some detail in the shadow
side (due to earthshine.)
* if OTOH, you're photoing things lit **by** the moon, then you'll need
to increase exposure by one stop above the loony F/4 setting for full
moon, then add 1/2 - 1 stop for reciprocity, depending on film and base
time, and then bracket.
George
Terry and Tracey wrote:
>
> > >> I would guess that since half a moon gives you half the light, then
> you'd
> > >> need to open up one stop.
> > >>
> > >Wouldn't half moon give 1/4 of the light?
> >
> > Am I missing something? Since the light is uniform across the moon's
> > surface, methinks the relationship is linear. I could very well be wrong.
> > Please enlighten me ASAP as tomorrow I have plans on shooting (although
> > it's a full moon....)
>
> Doesn't light "decay" at a square ratio? Hey, I could be wrong here.....
>
> Foxy
>
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