On Sat, 03 Aug 2002 06:26:33 GMT, "Tommy Huynh"
>"Lisa Horton"
>news:3D4ADC92.5ED6B346@lisahorton.net...
>> Remember Tommy, what works wonders at short distances becomes
>> innefective at longer distances. At 10' or more, any small
>> bouncer/diffuser is going to have minimal effect, if any.
>Naturally the effectiveness diminishes with distance but how much depends on
>the situation. I mean if you are in a large open space shooting at long
>distances, there's no question bouncing & diffusing will not be effective.
>I certainly wouldn't use it outdoors, in an auditorium, or shooting sports.
>However in closed spaces as when shooting indoors in a typical home, it's a
>completely different game. Here, you can use bouncing & diffusing to
>increase the area of your light source by using the large walls and ceilings
>themselves as part of your light source, and it will still be effective even
>at distances you described.
If the ceiling/wall reflective area is close/light enough,
this is true. But often you are dealing with 3-5' direct
to main subject distances, while the distance from the
flash to the reflecting surface plus the distance from
the reflecting surface to main subject can at the same
time easily exceed 6-8'. Adding in the 2+ relative stops of
light loss due to the greater distance, plus the loss due
to reflectance, you are looking at a relative exposure from
the bounce of 3+ stops under the direct light. Since an
underexposure this great is nearly equivalent to no
exposure, the bounce addition using this method should
be minimal and should make little or no change to the image.
It is hard to test this effectively, since to do so, you
must shoot identical photos, and remove the bounce
component from one... As I said earlier, if you can reduce
the proportion of direct light relatibe to bounce, this can
work, and is the idea behind bounce flash with a small
card used for front lighting.
>While the method of standing near a wall using a small diffuser may not work
>at 10' (I've never tried it at this distance), using a large inflated
>diffuser (like the bag method described) or tilting the flash and bouncing
>it off the ceiling at an acute angle certainly does. I shoot family
>pictures indoors all the time at distances up to ~15' using the translucent
>bag method and the results are very effective. It works not only because you
>are increasing the surface area of the light source, but because you are
>reducing the amount of direct flash while increasing the amount of "ambient"
>light reflected off the ceiling and walls. This reduces the highlight/shadow
>contrast ratio which is what you are really after in all of this. Yes most
>of the light using this method will still be from a direct source (the
>glowing bag) but it is distributed over a large enough area with enough
>scattered light to soften your shadows under most indoor situations (IME).
I think this is not true (see above), but under some
conditions, you will see the benefit of using the larger
source (and under unusual conditions, even the effects
you describe...). BTW, I often use a styrofoam cup over
the upturned flash, but this, as is true also with your
method, does not soften shadows due to bounce (or diffusion)
effects, and only softens shadows some when used close
to the subject - I use the cup to widen the angle of flash
coverage for super-wide lenses...