Haven’t we all shot landscapes where the blue sky turned out colourless or without detail, or the portrait with a bright background that just turned the face into a dark blur?
The reason is that most people prefer the imprecise outcome of the multi-segment metering mode, the one usually marked in safe green on the camera body, but the one that really should be marked in danger red.
If you understand how the TTL light meter in your camera works, you’ll learn to anticipate what shots will have a problematic exposure, really most of them, and it’ll save you some frustration next time you run into a difficult shot.
Especially when shooting film, but even if you are using a DSLR and have the ability to chimp and check the outcome of the shot on the on-camera screen, the exposure of the photo above will be difficult to realize in multi-segment or centre-weighted metering modes if you point the camera at the ceiling window and release the shutter: The bright ceiling window will be normally exposed and the underexposed stairs on the side will have lost all details in deep shadows and a wonderful opportunity is lost.
The camera’s TTL light meter usually gets blamed and when money is no issue an external light meter is acquired, yet the solution is simple if your camera supports spot metering and the locking of an exposure reading (usually a button marked AE-L.) And as far as I know, most modern DSLRs and film cameras support these powerful yet underused tools these days.
I can assure you that you get much better and much more predictable results by selecting the spot meter mode of your camera: Find an area in the shot that you reckon is a good approximation of neutral gray, meter this area and lock the exposure and bingo, you’ll have a great exposure. If you cannot find an area that is neutral gray, meter off a gray card and if you don’t have a gray card, meter off the inside of your hand.
Next time that you take a portrait and you’re not sure how the background is going to influence the shot: Walk up to the subject, meter directly off the face making sure you don’t cast a shadow, lock the exposure reading, walk back to compose the shot and shoot. Bingo, another well exposed shot!
It is as simple as that: meter, lock exposure, shoot!