On Mon, 05 Aug 2002 11:34:19 GMT, "Tommy Huynh" wrote:

>"Neuman - Ruether" wrote in message
>> 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.

>Here, I believe you are talking about using a small diffuser by itself for
>taking a picture in the middle of the room? I've never argued the
>effectiveness of a small diffuser in this situation.

?????????
Then we agree on this? I think, though, that the
term "diffuser" should not be used, since that
function contributes nothing to the image making...
My point above was that, under the most common
circumstances, the effects of pointing a flash
nearly directly at the subject, with whatever
paraphernalia is at hand (short a "real", large
softbox, or bounce off a BIG close-to-the-flash
surface), will be the same as not using the
paraphernalia, be it small bounce card, "balloon",
or whatever... (the exceptions occur when the
light source size is effectively and really
enlarged *considerably*, or when the flash is
used VERY close - otherwise, forget bothering
with the ineffective "diffusers", etc.

>> 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...

>I think there is a misunderstanding here about the method I talked about. I
>should have made it more clear. When you attach the bag, you need to tilt
>the head up ~60 degrees to not only reduce the amount of direct illumination
>from the flash (as I mentioned in the previous post) & provide more bounced
>and diffused light, but you have to because the bag will flop down in front
>of the lens otherwise. As I said, it works and works well.

Ah - this could work well (I saw before no indication
that you were using *bounce* flash with a widened
direct source - I took it that your flash was pointed
forward, and that would not have worked well...).

>I don't see
>much in common with this and your coffee cup method though. Not only does
>the bag give you a much larger light source, but it also puts more light on
>the ceiling where it is most effective in reducing shadows at longer
>distances.

I agree - that was my point: the cup "diffuses" the
light quite effectively, but this has little advantage
for softening shadows compared with the bare flash.
It serves *only* to broaden the angle of coverage
for super-wides... If your bag is transparent enough,
it could put most of the light on the ceiling, with
some "large-source" light directly on the subject
(if the bag is not too transparent...). Add in 1:1
available light (which permits upping the film
speed rating to almost double, with no change in
processing), and this technique could be a "winner"!
(The original post about the handkerchief over the
flash has none of the advantages of your technique,
though...)