Exposure Problem 5. Spot meter on
Although your camera’s spot meter can be extremely useful, if you forget that it is selected you can end up with some wild exposures.
The problem is that the spotmeter measures the brightness of a very small area of the scene and the camera suggests exposure settings that will render this small target a midtone.
If the spotmetering area falls over a highlight the exposure will be less than it should be and the image will be underexposed.
Conversely, if the metering spot is over a dark part of the scene the image will be overexposed.
The way to avoid such problems is to always remember to turn your camera back to the metering setting that you normally use – evaluative, matrix or multi-zone for example.
If you find that your camera is suggesting widely variable exposure settings, or that you have taken a collection of unexpectedly dark or light images, then check the metering method.
Special note for Canon SLR users
Canon’s iFCL metering system weights the exposure towards what is required by the subject under the active AF point and while this can be very helpful, in high contrast situations it can result in images that are much darker or lighter than expected. If this happens you need to use the exposure compensation system to get the image looking right.
Exposure Problem 6. Underexposed foreground in a landscape
A common problem in landscape photography is that the sky is often much brighter than the land beneath it and this can trick a camera into underexposing the foreground interest in your composition to make the sky look right.
Most photographers solve this problem by using a graduated neutral density filter (also known as an ND Grad) over the lens.
The filter should be positioned so that the dark part covers the bright sky, while the gradient (where the dark and clear parts meet) should be positioned along the horizon.
The filter effectively darkens the sky so that both it and the land can be accurately recorded at the same exposure settings.