The density of a photo or map supply us to many informations of land use and others.
The quantitative treatment as well as the qualitative is required in photo-and mapinter-pretations. It is necessary to determin the standard density in order to indicate the correlations between densities of many samples and is also necessary to establish method of automatic measurement and treatment in order to pick out the required informations.
The present paper is concerned with an establishment of the densito measurement system and with a classification of the base density by the reflection method into as many step as possible by use of the microdensitometer.
