多光谱摄影机底片灰标密度的辐射标定

为了在DGP—ⅡA型多光谱相机4个波段底片灰标的密度和所拍摄的地物辐亮度之间建立定量关系,自制并标定了相应于该相机4个波段的简易辐亮度计,用相机拍摄地标的同时,用辐亮度计测量地标的各波段辐亮度,在考虑底片光谱响应和滤光片透过率的情况下,算出了与底片密度对应的地标的辐亮度,因而标定了底片的灰标。

Radiant Calibration on the Gray Scale Density of Films in a Multispectral Band Camera

In order to establish a quantitative relationship between the gray scale density of films in model DGP-ⅡA multispectral band camera and the radiance of terrain subjects imaged on the film, we fabricated and calibrated a group of simple radiance-meters corresponding to the 4-spectral bands of the camera. When taking the photographs of the standard ground subjects, we at the same time measured their radiations for each band by means of the radiance-meters, then calculated the radiance of the ground subjects corresponding to the film density and calibrated the gray scale of the films with considerations of the spectral response of the films and the transmittance of the filters.