Wireless Flash (Speedlite type) HELP

Hello all Flash users.

I am going to be doing alot of wedding photography this summer, and I have a real good handle on flash/fill flash and when to use it....yet, my Flash (A Sigma EF 500 DG Super) has wireless capabilities. Now, i have NOT AT ALL jumped into the world of wireless flash photography...

Can someone who has a few minutes explain to me some practical situations where the wireless would excel over just a on the top of the camera flash. I dont have any umbrella equipment or light stands, but I would love to use this flash to its full potential...

I seriously thank you in advance if you can help me out with this!

Cheers,
David

On camera flash has the disadvantage that the light is coming from the camera. Off camera flash gives you the possibility to let the light come from where you want.
Some good tutorials here and off course here.

Strobist was the site that totally changed the way I look at flash photography. Regardless of where you're going with your photography, read it... you'll be inspired.

On-camera flash is head-on lighting, which can give a very "deer in the headlights" look to your subjects; it's very flat and gives no definition to the facial features. The moment you unmount the flash from the hotshoe and start trigerring it off-camera (using a PC cord, E-TTL, IR or RF) you enter a whole new dimension of depth and detail.

The caveat to all this of course is that, as a wedding photographer, you probably won't have the freedom to carry a lightstand around and "set up" your shots during the ceremony or the reception. You've got to be quick on your feet as it is, dealing with an off-camera flash may hinder that somewhat.

If you've got an assistant, have them hold the flash off and to the side for your shots - using an E-TTL cord will help ensure a proper exposure.

If you're working alone, investing in a quality flash bracket will still improve your results, not so much for depth and detail but for portrait-orientation shots as well as in avoiding red eye.

The bottom line is, the last place you want to put your flash is on the camera itself. Ironic, I know.