Patent ID: 7202892

Claim:
An image pickup method of synthesizing a plurality of images acquired by sensing an object under different exposure conditions to produce a single image excellent in gradation reproducibility, the method comprising the steps of: sensing an object under different exposure conditions to acquire a plurality of images; calculating a pixel value for each of the plurality of images; multiplying the pixel value obtained at the calculating step by a factor set based on the exposure condition to calculate a positive value compensation amount; compensating the levels of the plurality of images on the basis of the exposure conditions under which they have been sensed respectively, to provide a plurality of compensated images by subtracting the positive value compensation amount from each image; said positive valued compensation amount being calculated by multiplying a level average of each image of a coefficient based on the corresponding exposure condition; said coefficient being selected for each image based on the exposure condition of that image; synthesizing the plurality of compensated images to produce a single synthetic image having a wide dynamic range; and compressing the synthetic image to an extent depending upon the performance of its output destination to produce a compressed image.