To compensate for the curl resulting from the gelatine emulsion, a layer of gelatine was coated on the back of N.C. (Non Curl) film. Introduced in 1903.

Autographic film was introduced in 1914 by Eastman. It consisted of a spool of ordinary film with a backing paper which was not quite light-proof. Between the backing paper and the film was a strip of carbon-like paper. The two together forming a light-proof barrier to the film. A door in the back of the camera could be opened which exposed the backing paper, by writing on the backing paper with a stylus the carbon layer was disturbed and made no longer light-proof. The door was held open for a few seconds to expose the writing which then appeared in the negative.

It did not prove especially popular in use despite being heavily promoted by Eastman. The original idea was patented by H.J. Gaisman.

The image, right, show the extra carbon layer in an Autographic film. The images below show a camera for use with Autographic film and a negative.

These are for the original Folding Pocket Kodak of 1897. A stamp was to be placed on the end of the box and returned to Kodak.

Verichrome was a very popular material produced in roll-film and film-packs. It has a very wide exposure latitude partly due to the double layer of sensitive emulsion (fast on top of slow). In 1956 Verichrome Pan was introduced. The Verichrome name goes back to a plate introduced in 1904 by Wratten & Wainwright.

This is an extra fast panchromatic emulsion introduced in 1938 in 35 mm and 828 sizes as a replacement for SS Pan. Other roll-film sizes, sheet film, film-packs and 35 mm cine film were later available. Super XX roll-film was available until the mid 1950s. The speed in 1939 was 32° Kodak.

Panatomic X was a fine grain panchromatic emulsion. Introduced to replace Panatomic, at first in 35 mm and 828 sizes and later other roll-film sizes, film packs and sheet film. When introduced the film was rated at 27° Sch. (29° Kodak).

Introduced as a general purpose film in 1938, available in 35 mm MF and 35 mm cine formats. Roll-film was added around 1951

At first available as sheet film, later roll-film and 35 mm versions were added.

This is a lenticular process introduced in 1928 based on the patents of Keller-Dorian. Immediately in front of the camera lens is a filter consisting of three bands - red, green and blue - the film base was moulded into cylindrical lenses which formed an image of the filter on the emulsion. The effect was for the emulsion to contain narrow bands corresponding to the three filter bands. To project the image the filter was placed over the projector lens.

Kodacolor film required a tricolour filter (comprising red, green and blue strips) to be used over the lens of the Cine Kodak camera. A 'Ratio Diaphragm' was supplied with each spool of film which fitted over the filter to adjust the relative transmission of red, green and blue light, each batch of film was assessed to determine the diaphragm required, a number was stamped on the diaphragm, if this was different to the diaphragm already fitted then the photographer would have to fit the new diaphragm and discard the old.

Kodachrome was the first integral tri-pack colour film, it was introduced as 16 mm cine in 1935, the following year 35 mm cassettes and 828 roll-film was made available, cut-film was introduced in 1938. The familiar card mount for 35 mm slides was introduced by Kodak in 1938.

Kodachrome II was introduced in 1961 rated at 25 ASA, 15 DIN. A 64 ASA version was released in 1962. Kodachrome 25 and Kodachrome 64 were released in 1974.

The development process was extremely complex and, at least initially, carried out by Kodak.

Ektachrome was introduced in 1946. Unlike Kodachrome, Ektachrome incorporated the colour-couplers in the emulsion layers, this made processing much easier and could be carried by non-Kodak laboratories or processed at home.

The 127 roll-film size was added around 1959. Ektachrome-X was rated at 64 ASA, 19 DIN.

Kodacolor is a colour negative film for the production of prints. It was introduced in 1942 in roll-film formats and 35 mm cassettes in 1958. Kodacolor was not released in the UK until 1957. Kodacolor-X was released in 1962 in 35 mm (64 ASA) and then in 126 and roll-film.

The development process was intended to be carried out by Kodak.

The Premo film Pack was first sold by the Rochester Optical Co. in 1903. In 1907 ROC was integrated as a division of Eastman Kodak. From 1922 the packs were known as Kodak Film Packs.

Premo film packs were renamed 'Kodak Film Pack' in 1922, from the early 1930s they were designated 'Regular' to distinguish them from other emulsions then being introduced such as Verichrome.