Using strobes outside: balance ambient light w/stobes

[BaumannPhotography]

Hi guys,
I had been asked to do a family portrait session outside. There is a group of about 15 people. I took some practice shots the other night with my strobes outside, WOW, is that more difficult than I thought. I had the hardest time balancing the ambient light with the strobes. A lot of my shots were correctly exposed on the subject but were really dark on the background and everywhere else, looked like it was at night, when is was at 5pm and the skies were a little overcast but still not like what the picture look likes. Here is what I used for lighting:

2 strobes 240ws
1 w/ softbox to camera right
1 w/umbrella above the camera
sekonic L358

I had my lights about 6ft away. My question is how or what is a good starting point for getting a correctly exposed image. Where do I meter and how about the lighting setups? And I don't want to make it look like it was hit with a flash! Thanks guys

Adam

[poloman]

when you fire your strobes to establish exposure, look in the upper right hand corner of the display. It will tell you the % of the exposure that is flash. If you spin the jog wheel, that % will change. Experiment..... :)

[InspiredGraphix]

Keep in mind too that your flash output is only affected in exposures by your f-number.

If you are shooting through the middle of the day for instance, you would start somewhere around 1/125th @ f16 (sunny 16 rule). So you could either darken ambient down one stop (1/250th @ f16) or lighten it up (1/60th @ f16) and as long as your flashes were reading f16 at your subjects, then all would be ok.

If it is starting to get dark, try for something like 1/125th @ f11, ISO400 - 800. Ideally you don't want to open up more than f11 or you will run into DOF issues.

If you post your shots you did take, we might be able to offer some more advice based on what you actually shot.

Rob

[mblanton]

Adam,

I've been struggling with the same thing. This video covers the subject (key shifting) very well. Check it out.

Mike

http://www.youtube.com/watch?v=Xnn5nzPvoIM

[pickle1]

measure your ambient light with light meter.

let's say it is f/5.6 @ shutter 200

underexpose the background now by 1 stop and set it to f/8

Now add your flash(es) metered in @ f/8.

This would be your starting point.

You may even want to add a flash 12' behind group and point at them to help separate them from the background a little more.

Again, this is a starting point. You could use 1 flash at 5.6 and the other at f8 to add different layers of light.

You also could drag you shutter a little to bring up the available light. Say take a few pics at 200, then @ 125, then @ 60. The customer doesn't have to know that you are adjusting-- just keep shooting.

[Curtis N]

Pickle1 has it right. Start with what you can't control, which is the background ambient level. Meter this first and set your exposure accordingly. Then there are a multitude of ways to adjust the flash exposure of your subjects, by adjusting flash power, moving the lights, or shifting the exposure by adjusting the aperture with a compensating adjustment in shutter speed.

[Unity Gain]

I had my lights about 6ft away. My question is how or what is a good starting point for getting a correctly exposed image. Where do I meter and how about the lighting setups? And I don't want to make it look like it was hit with a flash! Thanks guys

Adam

It sounds to me like you just want a fill flash.

Once you setup your camera and find an angle on the subject....take a meter reading from the subject. Then, set the power on your flash units to be 1/2 to 2/3 of a stop less than your actual exposure. This will allow the flash units to kick in as a fill for the shadows. The ambient light will be your mainlight so your image will very natural....

Let's say your meter reading is F11
Then you'd want to set your strobes up for F 8-1/2 to F 8-1/3

This makes the strobes the fill light. It would be just like using a big reflector or a panel to fill the shadows.

[tim]

Studio strobes for outside family portraits? I wouldn't suggest that until you have the experience to know exactly what you're doing. How about using ambient light?

[sfaust]

I had written an article for my blog a while ago on balancing strobe and ambient. You can read it here (http://stephenfaust.wordpress.com/2007/07/14/balancing-stobe-and-sunset/) and see if it helps. I went for a darker moody background when I shot that, but the same principals apply. If you set your ambient exposure normally, you'll have a better balanced background.

I would setup the shot as explained here, or in my blog, then use the shutter speed control anywhere below your sync speed to vary the look of the background. For most images, I like the background within 1/2 stop plus or minus of the strobe. But underexposing will darken it, and overexposing will lighten it.