Metering For A Tiny Percentage Of The Viewfinder
Spot Metering (Pink Area Below) – I don’t know why but when I was starting out with photography as a teenager, I desperately wanted a camera with a spot meter, it sounded so professional. Now I have it, I rarely remember to use it!
Not all cameras have a spot meter; it is mainly reserved for the more professional cameras as the manufacturers know that it wouldn’t be used on many occasions by most people. Although now, many of the new breed of Digital SLR´s are starting to incorporate this.
What a spot meter does, as you can imagine from the name, is to take a meter reading from a specific part of a scene or subject. The metering is heavily weighted to the center (or pre-selected focussing point) covering just 3.8% of the viewfinder area (on average).
Let’s say you were photographing a huge barn on a sunny day and the main doors were wide open. Although the exterior looked well lit, the inside was still very dark, and the door area took up a large portion of the scene.
Using evaluative metering, the inside of the barn would stay pretty dark and the exterior would be perfect. But when using spot metering, you aim the center point of the viewfinder at the doorway, take a reading (and maybe hit exposure lock), re-frame and shoot, you would end up with a well exposed interior and probably an overexposed exterior.
With cameras such as the Canon EOS 1D MKII, you are able to take a number of spot readings (up to 8) from one scene and let the camera take an average reading and set the exposure accordingly. A great feature if I ever remember to use it.
TIP: If your camera doesn’t have spot-metering but you do have a zoom lens and exposure lock, try this;
Zoom into the part of the scene you wish to meter from, press the shutter release lightly to get a reading, hit exposure lock, zoom back out, recompose, focus and shoot. This does pretty much the same job! I use this technique quite a lot, it saves messing about with the meter settings.