Winsor,
One of the definitions of diffuse (verb) is 'scatter'. The scattering of the
light is not the culprit. What Acer and I were referring to in our discussion
of 'light loss' was that the material used is opaque, whether it's a plastic
milk jug, or alcohol bottle, or whatever, and not completely transparent. It
will not allow the same amount of light thru as if the light tube were not
covered by the plastic. The light output of the flash is, in effect, reduced.
Pros use big umbrellas up close because the light IS diffused by the
umbrella, which allows you to get the light closer.
I wonder if Acer could aim his camera at a large, bright light source and
take a camera meter reading, then still pointing at that light source, slip
the plastic over the lens and see if there's an accompanying dip in the meter
reading?
George S.
> I am not a flash expert, but I have read several articles that
> explain that the harshness of light is dependent on the size of the
> source and its closeness to the subject. If your source is the same
> size and at the same distance, diffuse or not, there will be little
> or no difference in the lighting of the subject. A couple of these
> articles have been illustrated with photos that demonstrate what they
> say. That is why pros use those big umbrellas and light boxes and put
> them so close to the subject. The light comes from a wide angle. The
> best you can hope for with something like that is that light will be
> deflected to walls and ceiling which will reflect some light onto the
> subject if the surfaces are near. You might take a more direct
> approach that would put more of the light on the surfaces that will
> reflect onto the subject.
>
>
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