Image-acquisition device for microscope and microscope observation method

A microscope observation method in which light from an object is branched off into two optical paths and images are acquired using a first image-acquisition element and a second image-acquisition element under different image-acquisition conditions, the method comprising:

• a first step of acquiring an image using the first image-acquisition element under a first image-acquisition condition with a first exposure time;
• a second step of calculating, in a case where an acquisition with the first image-acquisition element is switched to an acquisition with the second image-acquisition element, a second exposure time for the second image-acquisition element after a switching operation on the basis of the first exposure time before the switching operation and a ratio between the first image-acquisition condition of the first image-acquisition element before the switching operation and the second image-acquisition condition of the second image-acquisition element after the switching operation;
• and
• a third step of acquiring an image using the second image-acquisition element under the second image-acquisition condition with the second exposure time calculated in the second step,
• wherein one of the first image-acquisition element and the second image-acquisition element is used as a color image-acquisition element for acquiring a color image, the other image-acquisition element is used as a monochrome image-acquisition element for acquiring a monochrome image, and
• the ratio of the image-acquisition conditions includes a ratio of sensitivities of the first image-acquisition element before the switching operation and the second image-acquisition element after the switching operation.