Tuesday, February 07, 2012

Aspect ratios and letterboxes

click photo to enlarge
When, in 1839, Rowland Hill was given a two-year contract to run his proposed postal system with its "penny post", standard delivery rates independent of distance, post boxes and the rest, he cannot have known just how it rapidly it would be taken up across Britain, but also by the rest of the world. Nor can he have appreciated the employment that he would give to carpenters, joiners and handymen, and the changes that these tradesmen would wreak upon the country's front doors. Because the fact is, letters delivered to private addresses need to be left there securely regardless of whether or not the householder is at home. So everyone, in the fullness of time, needed a letterbox, and this was (in Britain at least) usually a metal framed slot with a hinged flap in the front door.

This kind of letterbox remains the most common way of receiving letters. Moreover, the word has become a generalised description for many things that have that distinctive shape that is much wider than it is tall, including photographs. In moving film terms it is used to describe widescreen shown as a "slot" in a deeper screen such that there is a border at top and bottom. In still photography it generally means a format or crop wider than 16:9 (widescreen) and closer to a panorama format (though that is a fairly elastic term.)

I think of the format of today's cropped photograph as letterbox-shaped. In fact, its not quite wide enough to copy the shape of a door letterbox, though it is wider than 16:9. In print and on the web this kind of shape is widely used. It enables an editor or designer to place an illustration where the space for the more common 3:2 or 4:3 aspect ratio photograph is limited, and it offers a graphic element that can form a segment of the overall page layout rather than be an insert into a portion of it. I value cropped, letterbox-shaped photographs because they are sometimes the best way of forming a composition out of a larger image. My original shot of Morley Lane in Bicker, Lincolnshire has too much empty white snow at the bottom right, too much of the upper branches of the trees above, and doesn't make enough of the two distant figures. The letterbox crop helps to alleviate those problems.

photograph and text (c) T. Boughen

Camera: Canon
Mode: Aperture Priority
Focal Length: 32mm
F No: f8
Shutter Speed: 1/80 sec
ISO: 100
Exposure Compensation:  0 EV
Image Stabilisation: On