If you examine this Built-in Flash mode screen, you will see that you have controls for the Built-in flash, and two groups or banks for external flash units. You’ll also see that you can set exposure compensation for either of these.

How would you use it?

Without going into great detail yet, let’s take a simple three light setup where the Built-in flash provides only a little fill-flash, Group A is the “main” flash unit, and Group B provides some background separation. Later we will consider in detail how you would configure the camera and flash unit’s settings, so don’t get stymied by the next paragraph. Right now I just want you to look at how easy it is to use the Commander Mode screen. Look at that screen above or in your camera, and then read the next paragraph:

First, you would set the “Built-in” flash compensation (Comp) to two stops underexposure to add just a little fill (Comp -2.0). Then leave the main light’s “Group A” compensation on Comp 0, and “Group B” background light’s compensation on one stop under (Comp -1.0). For now, leave all three Mode settings on TTL.

If you leave Custom Setting e4 – Preview Button Activates Modeling Flash set to the factory default setting of ON, you can fire your Speedlight’s built-in modeling lights by pressing and holding the D200’s depth of field preview button. Or, if you prefer, simply take a picture and look at it.

If the main light is too bright, you can either move it farther away, or dial its power down by setting Comp to underexpose a little. You can set Comp in 1/3 stop increments, so you have very fine control of each Group’s flash output.

My imaginary setup above may not work well at all. The point of this exercise is that you have control to experiment until you get the image just the way you want it. Sure, you could do things the old way, use a flash meter, or get your calculator and figure out complex fill ratios. Or, you can use CLS to vary your settings visually until the image is just right.

Isn’t it more fun to simply put some initial settings in your Commander Mode screen, and then take a test shot? If it doesn’t look right, change the settings and do it again. Within two or three tries you’ll probably get it right, and will have learned something about the performance of your CLS system. In a short time you’ll have a feel for how to set the camera and flash units, and will use your flash/camera combo with authority.

It’s about that time that your happiness will overflow and you’ll start buying flash umbrellas, light stands, and offer your portrait services to any victim … er, subject, that you can find — just for the fun of it!
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