The more I play with ceiling bounce, the more I like the results. It has certainly proven its worth on a variety of assignments, even in places where I thought there wasn't any way I could get enough light on my subjects. In addition, the ceiling bounce technique, coupled with the Black Foamy Thing, can help reduce glare from reflected light. Let me explain.
Because the flash head is aimed towards the ceiling, no light strikes the background directly. This allows the photographer free to adjust the shutter speed and aperture to suit the background, since the flash will influence only the foreground. In this sample, you can see that a Power Point slide is being projected onto a screen. Since I planned on using it as a backdrop, I adjusted my exposure so that the slide was well exposed. When the first speaker came to the microphone, I manually set the D7000 to 1/100 of a second at F 4.0, ISO 1600, Flash White Balance and took a test shot.
It is obvious that the proper exposure for background was underexposing the subjects in the foreground. So I turned on the shoe-mounted SB-800 with the BFT to prevent any stray light from striking the subjects head-on. Because the foreground subjects occupied such a small area of the image area, TTL metering was going to be unreliable. I started out by setting the flash to manual, and set the output to full power.
It's clear that the flash is doing some very heavy lifting, and you can also see the effect of light "splashing" back onto the projection screen, cutting the saturation and contrast. But I didn't get a "hot spot" that usually accompanies an on-axis light source. But the Power Point slide is still recognizable, and it provides the needed context for the photo.
One other advantage to ceiling bounce is the separation of the subjects from the background. The light, coming from above manages to completely illuminate the top edges of the subject. Granted, a light on a stick held high above the camera will also provide separation, but when using ceiling bounce, the edges are more rounded. I also liked how nicely the texture of Representative Speier's coat was rendered, something that would be completely lost if a more direct flash technique was employed.
All in all, I really like this technique. Sure, I don't get the same catch lights and eye detail I would have gotten had I taken a "light on a stick" approach. But for shots with multiple subjects, this is the ticket. One other important factor: my subjects did not appear to be bothered by the flash going off, probably because the light was directed toward the ceiling, exactly where the bright room lights were coming from already. There was a tremendous amount of flexibility in this technique since there was very little variation in the flash-to-subject distance. I pretty much just shot and shot, and only "chimped" the images occasionally.
I was using a 35mm 1.8 prime lens instead of my normal fixed aperture zooms. This lens gave a full stop of "free exposure", which improved the responsiveness of the auto focusing mechanism. Since I was using a D7000, the 35mm lens behaved like a 50mm on a full-frame camera. I was still using the single-servo mode with the center focusing brackets, and the results were some very sharp, well-focused images. There was a lot of scurrying to compensate for the fixed focal length, but it was certainly worth it. The aperture setting of F 4.0 was 2 stops down from wide open, so I gained a level of crispness that one sometimes sacrifices when fixed aperture zoom lenses are used.
Ceiling bounce is not "beauty light". Because it comes from high up, the light can't reach the eyes effectively. But it does produce a reproducible image, one that holds up well to printing on newsprint. It also looks like room light, since the shadows are under the subject, just where you'd expect them to be. Finally, the light does not appear to be as annoying to the subject as direct flash.