David Ashdown's sports picture diary: The Tour of Britain

David Ashdown was at The Tour of Britain race that passed through London this weekend. He explains the difficulties behind capturing such a fast moving sport and discusses a photographer's biggest nemesis - lighting:

Road cycling is a difficult sport to photograph, it may appear easy just to use a long lens with auto focus and blast away as they hurtle towards you. That's fine if all you want is lots of bikes that could be taken in any location.

But this was the first stage of the Tour of Britain which starts in London, and what is of prime importance is to show the race by placing it in recognisable locations, sounds easy - but it wasn't!

There are all sorts of things that get in the way of photography; the whole of the route had barriers down both sides of the road, lots of trees blocking the landmarks and the weather was grey and over cast when the race started. I walked some of the course to try and find somewhere that had all the elements that I wanted. Having decided on a spot by the Houses of Parliament, the trick was then to get the perspective of bikes and landmarks as balanced as possible, whilst also trying and get some sense of movement into the image.

On the first of ten laps I laid down in the road so I could put the camera under the barrier, and used a shutter speed of 1/500 second. It was all wrong, too low an angle, and a shutter speed far to high - the bikes looked like they were frozen with no movement at all, so on the next lap I tried hanging over the barrier and using a shutter speed of 1/50 second, better this time but still not right, the shutter speed was too slow creating too much movement on the bikes. The next lap I tried 1/125 second while still hanging over the barrier - it's just about right movement wise, but the light was not very good and it didn't look like getting any better. A bit of sun would have lifted all the highlights and transformed the picture.

Just after the peloton had gone bye for the firth time, blue sky started to appear, the sun came out and there were white fluffy clouds. Perfect. Only one problem - no bikes for at least nine minutes. I can't tell you how frustrating that is, you can feel that the weather is teasing you, almost saying bad luck mate, better luck next time.

As the minutes ticked down it started to get cloudier, the sun was in and out. It was one eye on the road for the bikes, and one on the weather. The exposure has to be set manually, because if left on auto the camera will pick up too much of the sky, and totally underexpose the buildings and road. So as the light keeps changing so does the exposure - it's old fashioned photography. The focus also has to be set the same way focused somewhere on the middle of the road, and with the aperture of the lens at F16 that gives a huge depth of field, in other words everything is going to be in focus.

As the peloton came by the sun was just poking through the clouds, a bit of blue sky on the left, and the dark clouds on the right seemed to balance Big Ben nicely. This picture is so much better because the light was so much better, it shows how important light is, it can literally make or break an image.

That's the wonder of photography - you never really know what you're going to get, so many elements are involved. It worked well this time, who knows about next time, but that's the fun and I wouldn't have it any other way.

Picture taken on a Nikon D3 camera at 1/125second with a 14mm lens at F16