580EX flash with Large Softboxes

Anyone here using the Canon 580EX with a large softbox (36x48x25") or larger?

I don't have any experience but I have heard/read that the 580ex, or most other flashes aren't going to have enough power. Having said that, I've send some people make their own setups and have had success. I guess it depends on how much light you want.

I'm sure someone out there has a definitive answer either way. I don't want to invest in monolights myself (since I don't have a studio and do mostly on location work) but would love to have a softbox. Right now I'm using an umbrella, not the same but still works good.

Whether or not it has enough power for you depends on how you will use it.

I've used a 580 in a large softbox, but generally only if I am shooting at the wider aperture range, such as f5.6 or less. It also depends how close the softbox will be to the subject, subject size, etc.

Generally, wider apertures, small subjects, and/or close to subject it might work perfectly for you. Smaller subjects, high apertures, or further distance will reduce its efficiency.

I'll try to take a meter reading the next time I use that setup.

Get it close to your subject and use high ISO and wide aperture, and you may be able to pull it off. It's definitely not going to be routinely practical, though.

Size of the SB does not affect the power output of the 580, subject to flash distance and what type of diffusion material and how many layers of it make the difference.

For a 3x4' softbox, the 580 need atleast a inner baffle plus the wide angle panel or Omibouhce to get close to even spreads on the front screen. That's 3-4 stops of light losts.

I use my 580 with a 24x36" sb sometimes, beside the low power, the quality fo light is worse than the Alien Bee because of the center hot spot.

A setup like this or this might work good. Good for places where you have no access to AC power.