One often hears judges referring to the shape of the 35mm format (3:2 ratio) as "the shape Mr Kodak dictates". However, the shape originally had nothing to do with Mr Kodak!
The format had its beginnings around 1912 when, in designing a motion picture camera, engineer Oscar Barnak at the Leitz Co in Germany, decided to build a small camera to test exposures on 35mm cine film. In order to produce negatives that would provide satisfactory prints when enlarged, (remember, film emulsions in those days were comparatively slow and would have much grain), he doubled the size of the cine frame from 18 x 24mm to 36 x 24mm by turning the camera around to produce the frame longitudinally along the film rather than across the frame as in motion picture film. These dimensions gradually became the norm for 35mm still cameras and are the standard today. So the standard was originally arrived at purely for technical, not aesthetic reasons.
Other artists, those who paint or draw for example, unlike photographers, are not bound by a fixed frame shape for their images. The problem for the 35mm photographer is that the frame shape can dictate the composition of the image in the production stage. By that I mean that in selecting the elements that will make up the final picture, the photographer will tend to use the attributes of the oblong format in order to compose the image. In addition, the small size of the viewfinder image forces the eye to select the image elements that satisfy the compositional demands of the oblong format by causing you to "fill the frame". This makes it difficult to change the composition later, particularly if drastic cropping becomes necessary.
Popular at the turn of the 20th century were stereoscopic photographs. These were made by combining two cameras into one by placing them side by side to duplicate the two eyes of humans. The problem of being able to view the image of the taking lens before exposure was first solved by using one of the lenses of the stereo camera as a viewing lens, placing a mirror at right angles to the light path and reflecting the image onto a ground glass screen. So that the image could be easily viewed, the camera was then turned upright so that the viewing lens was above the taking lens. Thus, the twin lens reflex camera was born. This would mean however, that if using an oblong format, turning the camera on its side would make viewing difficult, as anyone who has tried to do will attest. The solution was to use a square format which made the need for turning the camera for a vertical shot unnecessary.
The square format revealed quite a different way of photographic seeing.
Many subjects fit the square picture format shape very well. For example, a head and shoulders portrait is a natural for the square format. Square pictures are required for some purposes, for instance the covers for the old LP vinyl records (and CDs).
|Apparent unbalance can be remedied by choosing a square format|
Square pictures can always be cropped afterwards to give a horizontal or vertical format picture. This can be valuable for commercial purposes, thereby avoiding the necessity for the photographer who may be using a 35mm camera to duplicate an image in both vertical and horizontal framing for publication. With a square format camera, there is no need to turn the camera to obtain a vertical format - this can be done later during printing.
Cameras with oblong viewfinders discourage the taking of square format pictures. With such a camera it is natural to fill the frame with the subject. Therefore picture material which would fall naturally into a square shape is difficult to frame. Cropping the 35mm format to square format can mean sacrificing some 30% of the negative area, leading to a fall in image quality, especially when enlarged. However, cropped to 35mm proportions, a 6x6cm negative is still 57 x 38mm, twice the area of a 35mm negative.