I'm looking to get a diffuser for my Canon 580EX. However, the Sto-fen looks like somehting that the 580EX DOESN'T need. For instance, all it does is make the light pattern bigger and thus boucnes off more surfaces, which in turn makes the light softer and more even becsaue it is bigger. It also takes off about 2 stops, so the flash has to work harder and runs batteries down faster. Thus, it's useless outside. Also, the 580 has a pull out panel that increases flash to 17mm. And the 580 can swivels to bounce light also.

So my question is this: How would the sto-fen improve the quality of light on a 580? I'm thinking rubberbanding a white index card to the 580 in vertical mode would produce equal results and not cost more battery power?

visit http://www.abetterbouncecard.com/

watch the whole video - it's a long one - but well worth it. I use the rubber bands that hold broccoli together in the supermarket...

joe

Thanks Joe. I'll have a look.

"Softer" usually means more diffused and less specular lighting. Almost any, if not all, light modifiers that do that will reduce the flash "strength." It is hard to get something for nothing. (Thermodynamics says its impossible.)

Modifiers that bounce light are useless in situations (like outdoors) where there is practically nothing to bounce light off of. They also tend to color the light like the surface being used as the bouncer. Bounce a light into a red wall and get red light back.

On my flash units (not Canon), I use light boxes. They diffuse by making the flash area larger and cost power because the light must pass light through cloth. I carry a small one with my Norman 400B.

My wife likes to point the flash away from the subject and into an umbrella. Soaks up power, but makes for for very nice and contollable lighting. Can be used outside too. Not for the faint flash.

Howie, how big are said lightboxes?

I have three sizes. There is a smallish one, maybe 12x18" or so. Then the two largeer sizes are 2x3' and 3x5', roughly. I don't know for sure. They are just my small, medium and large. The medium and large don't get outside much. Stay in the garage mostly.

I have three of the medium and two of the large. I "stack" them if I need a really big box. I have four White Lightning 1800 units to power them. Plus an old Norman 400B.

The wife's umbrella is actually very nice. About 3' in diameter. Great light modifier, compact when not in use and cheap. And she has developed the technique to really control the output. Catches the wind pretty good outside though.

I have used sto-fens on all my flashes. They are only a slight improvement if used as instructed (angled up at 45 degrees). I find cutting a small piece of translucent white paper and spray gluing it inside makes a huge difference (pointed directly at the subject). It now becomes a portable soft box. I recently used the textured white paper from inside a CD/DVD sleeve with a slight dusting of basting spray. great results. If you need more light for telephoto or outdoor work just take it off.
Marc

The video Joe sent in his link worked great. You lose no power. And you do not have to bounce it to get a good effect. It simply makes the light source much bigger without costing light itself, or very little.

Your modification is interesting and worth a try. But have you tried dialing down the flash output power instead?

I also use sto-fens and find them work very well as a slight fill flash outdoors. I manually meter the camera, turn off the flash's ttl mode and dial down the flash by 1-2/3 stops. This creates the catch lights in a person's eyes and adds some shadow details without blowing out everything else.

Sound like what you you are doing is exactly what Canon's ETTL II does. As far as an outdoor diffuser, the 580EX, in my expereince, does not benefit from the stofen or any other scattering type technology, simply because there is nothing for it to bounce from. Thus, tehre can be no larger light srouce, and a larger light source means a softer light. Diffusion softens light by scattering it and thus making it bigger. The 580 outside will give a nice, even and soft look even taken front-on at about 4+ feet with no diffuser.

There is always the lightsphere

There is definitely something unique about the 580 that allows it to give fairly diffuse highlights.

That's my expereince. The foam home made diffuser seems to work the best for me and allows you to direct the light--although teh motorized flash head does a good job of that too. You will get much softer shadows using the foam diffuser, at least testing against a white wall and a subject in front of it.