PROBLEM TO BE SOLVED: To automatically set a lookup table suitable for respective images according to a color or fluorescent photographing mode. SOLUTION: The photographing mode is selected in a Step S1, and photographing is performed in a Step S2. An eyeground image is stored in a frame memory in a Step S3, and the lookup table is set according to the photographing mode selected in the Step S1 in a Step S4. Gradation is converted via the lookup table set by the Step S4 in a Step S5. Gradation converted data in the Step S5 is converted into a preset file format in a Step S6. The data converted into the file format in the Step S6 is recorded in a storage medium 25 in a Step S7. The gradation converted data in the Step S5 is transferred to a display memory in a Step S8, and is displayed on a television monitor 30 after D/A conversion.
