What is the difference between panchromatic and orthochromatic film?
Orthochromatic films were first produced in 1873. They are only sensitive to blue (and to a lesser extent green) light and are not sensitive to red light. This is why dramatically dark areas (that in reality are red) are often a distinctive sign of an ortho look. Their blue light sensitivity also tends to easily overexpose the sky in photographs.
Panchromatic films however, introduced in 1906, are sensitive to the full visible color spectrum up to 700 nanometers. Therefore they offer the most faithful reproduction of reality for black and white film, with a wide spectrum of gray shades. Most black and white film today is panchromatic.
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What are the different photographic film formats?
The three main types of film format are 35 mm, medium format and large format. More unusual formats also exist such as 110 and 127.
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What is tungsten film?
Most standard films are daylight-balanced, so they tend to capture the yellow-orange cast from tungsten lights. To address this, tungsten film was created to produce color-correct images taken under artificial lighting.
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What is 126 film?
126 film was launched by Kodak in 1963 as a way to simplify the process of loading and unloading film into cameras. Its name comes from the negatives’ dimension of 26.5 mm square. Although companies ceased mass production of 126 format around 2007 to 2008, its cartridge is still known and loved today.
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What is APS film?
Advanced Photo System or APS film was introduced in 1996 as a “high-tech” or modern alternative to the 126 and 110 film formats. It was 24 mm wide and it introduced many innovations, like the ability to choose exposure lengths and print sizes. Production of new APS film was ceased in 2011.
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How many layers does a film emulsion have?
There are several layers in a film emulsion and their characteristics vary with each manufacturer.
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How is the emulsion coating applied to the film?
The coating of a film is a layer of emulsion containing microscopic light-sensitive silver halide crystals.
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What are Silver halide crystals?
A silver halide is a chemical compound that forms between the element silver and one of the halogens. When the crystals are exposed to light they react and form latent images.
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How does film work?
A photograph is the final result that occurs when a chemical reaction exists between light and sensitive silver grain compounds.
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What is photographic film made from?
Film is composed by two main parts, the base and the emulsion. The film base is usually made of cellulose triacetate, acetate, or polyester. The emulsion is the active ingredient that will capture the final image.