How would you set your camera in this situation? Help!

I'm going to take a family portrait tomorrow, using my G3. We'll be outside (supposed to be partly cloudy) at a park. There's just two parents and two sons. We're doing this in the late afternoon, so not too bright of sun. I have a 420EX.

Normally I just use Auto, ( ) but I want to learn how to use the other settings. In the situation above, what would you set your camera at? (I know what aperture and shutter speed are, but I don't know how to use them correctly.) Would you use the 420, or just sunlight?

Please tell me exactly how you'd set your camera/flash and explain why you chose what you did. Thanks so much! I'm determined to figure this out! LOL

If you can have the sun to your back, no flash needed.

If you want more options, then use the flash for fill if needed, like if the faces are shadowed, or if it is sunny out and the subject is in the shade.

I often use P mode, as it lets you control things a little more if needed.

You can try and de-emphasize the background a little by shooting in Av, and using f2.0, then zooming out and getting as close to the subject as possible.

If the background is interesting, use a larger aperture so everything is in focus.

Try for a background that is appealing, but not distracting to the main subject.

My only addition to the reply above, is to make sur ethe shutter speed is at least 1/90 to ensure there's no movement.

I find that the G3's internal flash unit works quite well for outdoor fill flash every now and then. You may want to give that a shot - you may need to dial it down a few notches using the FEC setting under the "FUNC" button of the camera.

If not very cloudy I would have them about 90degree to the sun as shooting with your back to the sun means they will be looking into it and squinting.

Use your 420EX as fill in flash and use some sort of bounce that is suggested in other thread (stofen one has some advice). Take a number of shots ideally AV so you can control DOF, I would check images before they move off to make sure that no one has blinked.

Biggest focal length
Smallest aperture
I'd place them so that the sun is to their side. They wouldn't squirt.
Lowest ISO
The background is as far away as possible...

What's the sync speed of that cam?