Over And Underexposure. What, When And Why?

Aperture Priority, ISO 400, 32mm, 1/500s @ f/10, -0.7EV exposure compensation. (C)

    Have you ever taken a photograph of your daughter on her wedding day, and wondered why her wedding dress looked off white or even grey when reviewing the photo? Or perhaps a holiday snap while skiing in the Snowy Mountains and couldn't quite figure out why the snow looked dirty instead of the unblemished white you remember? Maybe at the other end of the spectrum, you've done some night time photography and the photo looked lighter than it should? Or perhaps photographed a stunning black racing car only for it to turn out a dull dark grey? Well that's because of how your camera's sensor meters the light. This is where overexposure and underexposure enter the equation.
    Remember photography is simply pausing a moment in time by capturing the light. Despite camera technology constantly improving and their sensors becoming more sophisticated by being able to discern colours more discreetly, the sensors still largely see everything between the extremes of white and black. Consequentially, they try to meter every subject as an average of the two or a "middle grey". That's why your daughter's wedding dress or your snow looks off white, or your night time shots look too light, or your black car looks dark grey. To compensate, you need to overexpose your predominantly white subjects and underexpose your dark subjects. But why would I overexpose something white when there's obviously a lot of light reflecting off it you ask? Or why would I underexpose a black car when it's already dark you ask? Remember as previously stated, your camera will try and turn everything into a middle grey. Therefore overexposing your lighter subjects will bring it back to white and underexposing your dark subjects will move them back to black.
    Take a look at the image of the beautiful 1968 Brabham from the recent Sydney Classic attached with this post. We underexposed this shot by only just under a full stop to maintain its wonderful dark colour. If we didn't, it would've looked too light bordering on grey and not been a true representation. The camera settings are in the caption. There is also an artistic reason for underexposing as well. Underexposing is useful for bringing out the riches of colour as well. Handy if photographing flowers, sunsets or motorsport for that matter. 
    While we have never professed to be photographic experts, we hope these tips help and remember, these tips mainly concern DSLR camera users. Check out our Final Sector page, click on the images and you'll see our camera settings to further spark some ideas. Happy shooting....
    

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