Image capturing apparatus and control program for the same

A control program for an image capturing apparatus which includes a setting unit configured to enable a user to set an aperture amount of a lens unit controlled by a stepping motor, an accumulated time of an image capturing unit for receiving light from an object image passed through the lens unit, and a gain of a signal from the image capturing unit, as control values, a display unit configured to display the control values, an obtaining unit configured to obtain an aperture value of the lens unit based on luminous information of the object image and the control values set by the user, and a calculation unit configured to calculate a control signal for controlling an aperture of the lens unit according to the aperture value obtained by the obtaining unit, the control program comprising:

• when the aperture value of the lens unit obtained by the obtaining unit based on the control values set by the user is a first aperture value, causing the display unit to display a value based on the first aperture value, and causing the calculation unit to calculate a signal corresponding to the first aperture value, and when the aperture value of the lens unit obtained by the obtaining unit based on the control values set by the user is a second aperture value, causing the display unit to display a value based on the second aperture value, and causing the calculation unit to calculate a signal corresponding to a third aperture value which is different from the second aperture value.