A charged particle radiation device wherein the position or the size of a FOV can be easily determined even if a number of measuring points are provided on a sample, and an image capturing condition determining method using the charged particle radiation device are provided. An image capturing condition determining method wherein the field of view of a charged particle radiation device is determined so as to include a plurality of measuring points, characterized in that whether or not the measuring points are overlapped with four sides of the field of view is judged; the field of view is moved so that the measuring points are moved to the inside or outside of the field of view; and the position of the field of view after being moved is determined as a position of the field of view of the charged particle radiation device, and a device to realize the method are proposed. Further, a method for judging whether or not the measuring points are overlapped with the four sides, and changing the size of the field of view so as not to overlap the measuring points with each side, and a device therefor are proposed.