Flash - advice needed

[martcol]

Hi All

10D + 550 EX & 420 EX Slave.

I'm trying to do some portraiture, outside, using my 550 on camera and the 420 on a tripod. I find the 550 pretty cool any way but thought if I slaved the 420 to the side, it might put a bit of detail back in. Hmmm, however, the difference is not that great. Any help? Also, if you have plenty of ambient light and two flashes, should I AWB or go for flash White Ballance?

Next: I'm using my 50 mm 1.8 lens and want to open it right up for max DoF but the 10D doesn't like it, keeps setting shutter 200 and the images blow out. So, how do you set a large aperture, plus flash, shooting in daylight?

Finally, different situation. At an outside event running from bright afternoon to dark I used my 550 EX on camera through most of it. During late afternoon all photos caught the rich orange glow of the setting sun. As things got darker, I notice an increasing red cast on most shots (worse if slightly under exposed). should I use the flash White Ballance there?

Thanks

Martin

[RajaBhat]

Martin,

The *dominant* light is the white balance setting you should use. I have done studio portraits with studio flash, and auto white balance does not come out right. Have to choose flash white balance for that. Outdoors with enough ambient light, I guess auto white balance ought to work OK...I'd take a shot with each white balance and see which is more accurate.

You used the 550 as a head on flash, and the 420 on the side really won't make much difference....you'll really have to invest in an ST-E2 and have the 550 as the main light to one side, and the 420 on the other side...

Raja

[daveh]

martcol wrote:
Next: I'm using my 50 mm 1.8 lens and want to open it right up for max DoF but the 10D doesn't like it, keeps setting shutter 200 and the images blow out. So, how do you set a large aperture, plus flash, shooting in daylight?

Maybe just a typo but that's backwards. You close the lens down for lots of DoF and open it for little. Of course, if you open the lens a lot with a flash, you have the flash sync speed limitation so you have to control your ambient light - ND filters will work. Then again, if you really wanted max DoF - ignore that and go the other way.

martcol wrote:
As things got darker, I notice an increasing red cast on most shots (worse if slightly under exposed). should I use the flash White Ballance there?


This is going the wrong way too. If things look too blue, then using the flash WB might help. You might tried shooting a grey card and white balancing on that. (Assuming you don't want sundown shots to look like sundown shots.)