I don’t use a light meter all the time. In particular when walking around renaissance festivals or moving around a lot outdoors when light direction and clouds are changing, I stick to Aperture Priority (Av on the Canon dial). However there are times when flipping things into full Manual and using a light meter is the way to go.
Basically when your light is going to be consistent and not changing much during a shoot.
Case-in-point: The Combat Tournament of Sherwood asked me to take some shots of them earlier this year prior to the opening of Sherwood Forest Faire. The faire grounds in February have lots of dappled light in the shade under trees (no leaves yet) and the shoot would be mid-day. (Isn’t it always that way? 🙂 )
Scouting around I found a patch of shade on the side of a building. It was basically big enough to allow 1 person to stand almost with their back to the wall and they would be in complete shade. If they moved a step forward, they would get direct sunlight on their hand, nose, weapon, whatever was in front of them. Here’s an idea of how small the space was.
Using my trusty Gossen Digipro F light meter I took an incident meter reading of the ambient as 1/125s at F/4 ISO 100. The ambient light shot is pretty flat. But once I know ambient I can build off that and use the ambient as the “fill” or base light in the image.
First thing I wanted to try was “clean up” the color cast in the image. Simple first idea was to use on-camera flash (GASP!), in this case my Canon 580 EX II speedlite with flash exposure compensation at -1 stop, camera was in Manual 1/125s at F/4 ISO 100. This made the image better, but it’s still pretty
flat blah lighting-wise.
Off to camera-right was a place where I could setup a speed-lite on a stand (actually used an old Nikon SB-26 flash I bought used with a radio trigger), flash was in manual mode for power settings, zoom, etc… works brilliant. I was shooting with a Canon 40D, but with simple radio triggers and flash in manual, it doesn’t matter much what the remote flash is. Just that you know how to manually set its output.
In this case I wanted to give the light direction to add some drama to the scene. I removed the on-camera flash, put the radio trigger in the camera’s hot shoe. Knowing the ambient light reading from my earlier incidient light meter reading was 1/125s at F/4 ISO 100, I could use that as my “fill” or base amount of light in the shadows.
Then I powered up the SB-26 and took incident light meter readings until it read F/11 at the subject’s standing position. That’s 3 stops “hotter” than the ambient light F/4 -> F/5.6 -> F/8 -> F11 so camera settings in Manual mode were changed to 1/125s at F/11 ISO 100. No light shapers on the flash, I wanted hard light for this.
Viola! Now we’ve got a picture with some attitude going on. All with 1 flash and knowing what your base ambient exposure is.
The function of the light meter? Speed! Instead of burning a lot of my talent’s time with lots of test shots to dial in an exposure, I got to final settings in many fewer test shots (4 actually) with the meter. Probably could have done better, but without the meter it would have taken me significantly more shots to nail final exposure.
Thanks go to the members of the The Combat Tournament of Sherwood for allowing me to use them as
guinea pigs subjects in this shoot. 🙂