Thursday, December 28, 2006

No cuttlefish harmed!

click photo to enlarge
This photograph is not sepia-tone. It shows the colours as they came out of the camera, and the brown hue is entirely natural. Well, as "natural" as any colours can be that are recorded by the sensor of a digital camera.

The original sepia-tone, as seen in countless late nineteenth century portraits of Victorians, came about through the desire to make photographs less prone to fading. Interestingly, 2006 was the year when modern printer pigments surpassed the longevity of traditional, silver-based printing. Images can now be made that will resist fading, it is calculated, for 200 years. The introduction of the original sepia colour in the 1880s followed the discovery that adding dye from the common cuttlefish (Sepia officinalis) to a positive print increased the durability of the photograph. This worked by converting any remaining metallic silver to a more resistant sulphide. The consequent brownish cast was, depending on your point of view, a pleasant or an unfortunate consequence of this technological advance. Quite why some contre jour photographs taken with modern cameras produce this sepia-like effect I don't know. What I can tell you is that no cuttlefish were harmed in the production of this image!

I took this photograph on Blackpool's North Promenade on a fairly recent sunny afternoon. The light was emphasising the curve of the tram tracks as they straightened up and disappeared into the distant vanishing point of the Tower. Shapes, particularly the tram poles, the overhead booms, and the receding blocks of the nearby wall, made strong silhouettes in the contre jour light, and increased the focus on that distant point. But, foreground interest was needed, so I asked my wife to walk ahead! I used a zoom lens at 92mm with the camera at Aperture Priority (f6.3 at 1/1250), ISO 100, with -0.3EV. The post processing mainly involved increasing the contrast.
photograph & text (c) T. Boughen