In article <4bvp3k$lan@cello.hpl.hp.com>, jacobson@cello.hpl.hp.com says...
>In article <4bvcqv$1mn@newsstand.cit.cornell.edu>,
>Bob Neuman wrote:
>>I have written a bunch about flash add-ons in the past, but the gist
>>is, I'm agin em - theyz purdy worthless. I do find a styrofoam cup
>>inverted over the upturned flash head useful for losing light when
>>shooting close with fast film, wide apertures, and a powerful flash.
>>It is also useful for widening coverage for super wide angle lenses,
>>and for getting the flash above the lens with verticals and on-camera
>>flash. Forget about "diffusion" - it is a myth.

>I'm foolish for arguing with David R. (Bob Neuman) but here goes.
---Naw, go right ahead - I have actually been known to be wrong on ---occasion (It has been documented! ;-)!
>I've never used the Stofen, so I can't say anything about that.
>But if you are saying that flash add-ons in general are worthless, I
>strongly disagree. I've got several LumiQuest gadgets and love them.
>1. The 80-20: Truly wonderful. It gives very soft nice light without
>those dark eyes you get with just bounce. I just love it for causual
>pictures of family fun in the kitchen. I've got wonderful pictures of
>my daughter carving pumpkins, dipping candles, etc.
>2. The BigBounce: Great for macro stuff. I put it on my Nikon SB-24,
>and connect that up with the SC-17 sync cord, and hold it right over
>the subject. (...)
>3. The Pocket bouncer: I use this one least of all. It fits easily
>in my camera bag and the BigBounce won't. So I sometimes use it for
>macro stuff if I'm limited to just the camera bag.
---Seems to me that you have found the times when add-ons DO work
---(to fill low ceiling bounce, and for close work) - though paper ---sheets, small cards, and styrofoam cups are cheaper than the ---commercial products. In my haste to abbreviate the reams of blather
---I feel like I have posted on the subject of useless flash add-ons,
---I neglected the useful ones, which you have pointed out.
>Now, let me say some things in agreement with David. Most people seem
>to think that those things diffuse the light. I think that the only
>way to get diffuse light is to get it coming in from a lot of
>directions. In the macro case, this works because the BigBounce is
>close to the subject relative to its physical size. The case of the
>80-20 works because most of the light bounces off the ceiling. The
>styrofoam cup or the Stofen may work because a very large fraction of
>the light gets to the subject via reflections rather then directly.
>But, except for the BigBounce in macro work, the physical extent of
>those things is not enough, by itself, to get diffuse light.
---Ditto on everything above, accept the comment on the Sto-Fen -
---unless the reflecting surfaces are VERY near the flash, the
---reflected light is insufficient to make much difference in the
---photo (the light source is still the flash, and its size is not ---significantly larger with the add-on). Guess we agree!
> -- David Jacobson
---Hope this helps.