Of emulsions and equipment – the early years

The camera came before film

The Camera Obscure (translated as “dark chamber”) dates to around 1021 when it first appears in print in a work by a Muslim scientist Ibn al-Haytham, and it was little more than a sealed room with a pinhole in one wall which admitted light reflected from the scene. An artist could then trace the projected image onto a canvas as a starting point for a painting – perspective was not well understood at the time. The image was laterally and vertically reversed.

The simplest of early cameras also used a pinhole design, projecting the image onto a plate which was the same size as the finished print.

Glass plates and room sized cameras

In the early part of the 20th Century photographic chemistry was comparatively crude. Emulsions were not very light sensitive, meaning that large surface areas were required in order to expose enough of the material to light – more surface area captures more light. This had several consequences:

  • The camera had to be physically large, which itself meant added expense
  • Photosensitive plates were large, which was also expensive
  • You need a helper to cart all the equipment around

As a consequence photography was largely the province of the well heeled or portrait artists. Equipment was big, expensive, hand made and required lots of time to setup and operate. Look at photographs from the late 1890’s through to 1920 and you’ll see little that is spontaneous or casual; making a picture was an undertaking.

Faster film on a flexible base

A large film media requires a large image circle, which in turn results in a lens that’s sited further away from the film plane – and as a result the whole light box that is the camera must itself be large too. Various techniques were tried to combat this, most common being the bellows unit and folding or collapsing lens mechanism. Although invented in 1885, the flexible, transparent film as we knew it was not widely used until 1910 or so – this was another major step forward in democratizing access to photography, as now a separate, expensive, glass plate was not required for each image.

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From the 1920’s to the 1940’s several things changed; film emulsions became more sensitive which lead to the ability to use smaller negatives, and manufacturing techniques scaled up thus reducing unit costs. Across every sphere of human industry manufacturing was automating, and every manner of manufactured item was becoming more economical and accessible.

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