A simple straightforward guide to the different camera exposure metering modes and tips on when to use each one.
So as we know – photography is the recording of light and how well we are able to do this this through the camera will greatly affect our photographs. Too much light and our images will end up too bright and over-exposed and too little will result in dark under-exposed areas.
How do we control the exposure and amount of light?
Well as we have seen earlier we can control the amount of light with our aperture, shutter speed and ISO (please click on these terms to see my earlier articles on these respective topics). Whilst these can help us change the amount of light entering the entire scene, they do not allow us individual control to specific parts of the scene that we are trying to photograph.
When it comes to tricky lighting scenes that we are trying to photograph, we can also utilize our cameras advanced metering modes to help us meter the light in the scene correctly and take a well balanced and correctly exposed photograph. So you may have seen some of these options on your camera’s control menu and not really understood what they meant. I will tackle each one in turn.
Your Camera’s Metering Modes Explained:
Multi-Zone Metering is also referred to as Evaluative/Matrix Metering depending on camera brand.
This is usually the default metering mode on your camera and works effectively on the majority of scenes. The camera divides up the area into sections or zones and meters for each of these individually giving the camera a more detailed reading of the overall scene. The technical calculations that the camera makes are based on the information it takes and what is stored in the database within it, so it knows which areas to give priority to and which to ignore.
Center Weighted Metering
This is a pretty straightforward mode where the camera will meter the entire scene and then place the emphasis on the central part of the image. The camera will prioritise the main central part of the scene, usually around 60% of the viewfinder. This mode is useful where your main focal element is in the centre of the lens/scene and where there is a particularly bright or dark element in the foreground or back of the scene that may confuse the multi-zone metering system above.
However, it is important to be aware with this mode that if you focus and then recompose before you take a photograph (where you half press the shutter on the focal point and then re-frame your image), your exposure mode will still have taken the reading from the earlier centre of the image and will not have the opportunity to re-calculate for your new framing. This will risk having incorrect exposure readings.
When using spot metering, the camera will read a small percentage of the scene based upon where you point the camera at/focus on and then calculate the correct exposure based upon this information. This mode is particularly useful where you want the camera to calculate the exposure based upon a specific area of your scene and prioritise this as the main exposure point for the image.
Often, the spot metering is linked to the chosen auto-focus point that you may have chosen for ease of use.
Other important considerations
Although your camera meter often produces impressive results, sometimes it can get confused, especially where there are extremes ranges of all light or all dark scenes.
Remember, your camera can’t see what you can and sometimes you may need to use your exposure compensation to correct any mistakes it may make. Underexposing snowy scenes is a common camera error where the white snow is underexposed to produce grey snow. You can click here to read my earlier article on exposure compensation.
Once again please feel free to contact me if you have any questions or comments about this post (or anything else on my website), and to pass this tutorial onto any photographer friends you think may benefit from it.
Until next time!
Thank you for this interesting article Antony. I keep making the error of having bright spots in a scene over-expose (i.e. a brighter spot in the sky in between buildings for example) which I am not noticing until I process the images. Can you advise how best to avoid this in future during shooting? If I exposed for the sky, the buildings would be too dark presumably? Appreciate any tips you can offer.