Low speeds and high grass

Photography has a set of unofficial rules, repeated frequently by the monthly camera rags under different headings to fool you into believing there is something new to be read. One of these rules states that you should keep your shutter speed higher than the focal length of your lens. This assumes that you actually know the focal length of your camera, or actually give a shit about producing a photo which has any degree of sharpness. Judging on output, Billy can stop reading now, although I am sure his fragrant and talented wife knows exactly what I am talking about.

So if your lens is 50mm, keep your shutter speed higher than 1/50th second. 150mm; more than 1/150th second; and so on. All this assumes your subject is static. If it is moving, then other considerations come into play. Polo, for example, has a horse moving vertically and horizontally at the same time. I shoot with a 300mm lens, but 1/300th second is not enough to give a sharp image. So I use 1/640th which is fast enough to freeze the rider and most of the horse, but still provides some blurring of the hooves and lower leg to give a sense of action.

So if you look closely at this shot:

The rider and body of the horse are sharp:

But the legs are nicely blurred to reinforce the sense of movement:

Bikes present a different problem. Apart from some general vibration in all directions, they tend to confine themselves to a horizontal direction. So shooting at 1/400th with a 300mm lens produces a sharp image, like this (although you still need to pan the shot accurately to get a sharp result):

Warning: if you click on these bike shots you will see larger images than usual.

But while you are more likely to get a sharp photo, the result can look a little static:

So, you have to break the rules and drop the shutter speed. Accurate panning becomes even more important and you will throw away many more than you keep.

1/250th:

1/200th

1/160th

1/125th

Hard to capture at these lower speeds, but it looks good when it works.

But there is another problem with shooting bikes at Bira, and you can see hints of it in a couple of the above shots; and very clearly here:

Looks like a delinquent child has ruined an otherwise awesome photo by scribbling on it with green crayon. But it’s grass. The inside of every corner of Bira is covered with thick grass, such that it can feel more like you are on safari rather than at a race track.

I’m going to buy a strimmer.

All the bike shots taken yesterday when the Honda racing team were in town with both Thai and Japanese riders. I have the dubious distinction of being told off by the head of Honda racing for standing in a dangerous position on the outside of one of the fastest corners. He was right, if the bike had crashed, I would have been killed. Still, I did get a nice shot from that position:

Shutter speed was a bit high though, will have to go and take it again when “Mr. Safety” is not looking.

Comments 🔗

2010-02-26 | Jock says

Thanks for the lesson … the 1/125th shot looks truly superb to my untrained eye .. I’m just a point and click kinda guy.

2010-02-26 | Billy says

I should indeed have stopped reading at that point, now my head is spinning from all those numbers and I shall now have to go and lie down … and not read a photography mag while doing so …