WHAT IS DYNAMIC RANGE?
Dynamic range is at the heart of exposure theory, and nowadays it’s much easier to measure
test the dynamic range of Nikon D-SLRs as part of our reviews.
In both cases, dynamic range is measured as EV values, or ‘stops’, and the secret of exposure measurement with your D-SLR is to try to make sure the dynamic range of the scene you’re shooting isn’t greater than the dynamic range of your camera. You also need to learn what you can do to fix things if it is.
Fortunately, you don’t have to get caught up with f-stops and exposure values and complicated calculations, because your camera’s histogram display can tell you everything you need to know at a glance. Our diagram opposite shows you how to interpret what your histogram display is telling you.
Old methods, old problems
Digital SLRs come with a selection of metering modes to help you get the exposure right. Matrix mode will analyse the whole scene, centreweighted mode will average the light but pay more attention to the centre of the scene, and spot mode lets you base the exposure on a small area.
All three metering modes have their uses, but they’re all designed to achieve a balanced-looking exposure – they don’t measure dynamic range. They can all produce shots where the highlights and/or shadows in the scene are lost.
In a way, these metering modes are a throwback to a pre-digital age, whereas we can now measure and see the dynamic range of a scene very easily. So you can stick to your current ways of working out the exposure by all means, and most of the time they’ll work fine. But there will be situations where an understanding of dynamic range, and how to read it digitally, can produce pictures with a range of tones that you might not have been able to achieve otherwise.