Some Aspecs of Colour Aerial Photography in Practice and Its Applications

Abstract

An attempt is made to review the factors affecting the use of colour photography in photogrammetry and photo‐interpretation. Examples of current practice and results of comparative tests are quoted, as well as the advantages and deficiencies of the various materials available.

Aspects of Comparative Air Photo‐interpretation in the Dyfi Estuary

“…Colwell (1960) indicates that such prints "are not so good as those made from panchromatic negatives", although they are quite suitable for use in field checking. Rees, in a paper by Mott (1966), is quoted as saying that in Malawi such prints were "in this case markedly superior to those from the panchromatic film. This might be peculiar to this particular sortie."…”

“…In the identification of natural vegetation there has been some disagreement on the relative merits of colour, false colour and panchromatic photographs (e.g. Mott, 1966;Mangles, 1966;Woodrow, 1967). In the interpretation of bracken there seems to be little gained by using colour and false colour films since the tone and texture of such areas are normally sufficient on panchromatic photographs for them to be positively identified.…”

“…In the uses of reversal or negative materials both Mott (1966) and Woodrow (1967) have summarised the advantages and disadvantages of the two systems. For interpretation the negative system, by virtue of the greater control which can be maintained over the colour balance of the final photographs, appears superior.…”

Film Trials of Aerial Photography for Forestry in Victoria, Australia

“…By 1967 only scant local knowledge was available on the techniques and value of using aerial films other than conventional panchromatic black and white films. This may seem surprising since the first aerial colour films were produced in 1942 (Tarkington, 1953), although photographs of high quality were not produced until the 1960s (Mott, 1966). Even then, traditional prejudices retarded progress, with many disadvantages being claimed against colour.…”

“…The points for and against the use of negative versus reversal films have been well summarised by Mott (1966). For most photography, the exposure and processing of negative film are less critical and it has nearly all the flexibility of a black and white material.…”