Photographic system Characteristics of photographic system

The photographic system is mainly used for visible light remote sensing, and it is divided into black and white panchromatic photography, color photography, infrared photography, color infrared photography and multispectral photography according to the working band, that is, the combined form of color filter and photosensitive film (the working band includes part of near infrared spectrum).

The photographic system has the advantages of high resolution, good geometric accuracy and simple photographic processing. Its disadvantage is that the working band is limited and cannot be subdivided, only 4 ~ 6 bands; Due to the use of film recording and the change of photographic processing conditions, the image density is difficult to quantitatively reflect the electromagnetic wave energy of the corresponding ground objects, which is not convenient for quantitative interpretation and computer-aided classification. The registration accuracy of images in different bands is not high, which reduces the definition of synthetic images.