Thursday, November 03, 2011

Wide angle distortion and innovation

click photo to enlarge
The flood of innovation in cameras and photography in general that occurred following the introduction of digital into the mass market continues, albeit at a slower pace than five or ten years ago. Most recently we've seen developments such as the Lytro camera that allows you to select a point of focus after you've taken your shot, or produce versions of the same shot with different points of focus. Interesting though that is, it's not the first new development that I would wish to see. In fact, way ahead of such things I'd place a means of controlling wide angle distortion.

I was thinking about this the other day as I photographed the church of St Botolph in Boston, Lincolnshire. I've posted shots of the exterior of this building before (for example here, here, and here). These distant views show the tower or details, but not the whole of the church. That is because St Botolph is one of the largest parish churches in the country, its tower is the tallest (that doesn't include a spire), and it is quite closely surrounded by buildings. The only "open" shot you can get of the church is from a space near the edge of the market place. However, from this location a wide angle lens is necessary, and with that comes distortion that changes the emphasis of the component parts of the structure. More specifically, the tremendous tower with its "lantern" top is diminished in size and the nearness of the chancel causes it to assume a bulk approximately equal to that of the nave. Such equality of size is rare in an English church and it certainly doesn't exist at Boston even though its chancel is bigger than that of some cathedrals. If the photographer was able to somehow adjust the distortion that the wide angle lens produces and could bring a building closer to its proper proportions I'd be very happy. You may well think that to do so would break the laws of optics. But wouldn't we once have said that about selecting a point of focus after the shutter has been pressed?

The sharp shadows produced by the clear sky of an early November day prompted this shot. I usually wish for a few clouds when the sky is clear, but the searing blue of this autumn day also had its attractions, and without it those sharp shadows wouldn't have been there. Incidentally, in the photograph Herbert Ingram standing atop his column once again has the indignity of a bird perched on his head. Whenever I pass there's usually a pigeon in residence. On this occasion it was a black-headed gull that had claimed the prized spot from which to survey the world and scavenge for crumbs.

photograph and text (c) T. Boughen

Camera: Canon
Mode: Aperture Priority
Focal Length: 17mm
F No: f6.3
Shutter Speed: 1/400
ISO: 100
Exposure Compensation:  0 EV
Image Stabilisation: On