A lens device (2) is provided with a first operating ring (11) for adjusting the opening surface area of an aperture device (15) and a second operating ring (12) for adjusting the transmittance of a variable light transmittance filter (16). The correspondence relation between the operational amount for the first operating ring and the rate of change in the amount of light transmitted by the aperture device and correspondence relation between the operational amount for the second operating ring and the rate of change in the amount of light transmitted by the variable light transmittance filter are the same.