Sunday 25 May 2008

Shooting interiors with high dynamic range

For further photography-related information check out my compendium of tips.

I photographed Chris and Sue's wedding in Folkestone at the Burlington Hotel last month. The hotel subsequently asked me if I could shoot some interiors for them so I went along this afternoon. I decided that this would be a perfect opportunity to use high dynamic range (HDR), illustrated by the shot shown above.

The human eye and brain can deal with a huge tonal range - you take it for granted until you start doing photography and then realise how limited cameras are. It can be a bright sunny day but you can see still detail in the sky near the sun and the shadiest spot under a tree - and all at the same time. Estimates suggest that human vision can deal with over 15 stops of light (bear in mind that 'one stop' means doubling the amount of light so this means a tonal range of 2 to the power of 15 - very impressive). Cameras can deal with only about 6 stops of light - shooting RAW allows another 2 stops to be reclaimed with digital processing. To really start expanding this you need to combine more than one photograph (or alternatively, as landscape photographers do, you compress the tonal range by using a graduated neutral density filter). So for the above shot I set my camera on a tripod and then took 3 photographs - one at the exposure metered by the camera, and then one at -2 stops and one at +2 stops. The hard work is done by a piece of software called Photomatix Pro which combines the three shots into one by a process called tone-mapping (Photoshop can also do this but the batch-processing feature in Photomatix is a real winner). It's great fun but try and exercise some restraint - it's very easy to overcook the effect!

No comments: