This paper proposes a novel iris image capturing system using a pantilt-zoom camera for unconstrained user environments at a distance. To provide wide operating range, we are trying to develop iris image acquisition system using pan-tilt-zoom camera. This paper verifies that iris recognition is possible when iris images are captured with zoom lens at a distance from camera. Iris images are collected by changing the distance from camera to user, zoom factor to maintain face size in an image, and focus lens position. And they are assessed by Hamming distance. Experimental results show that iris images captured at a distance of 1.5-3 m from camera can be verified as genuine and proposed system has 5-10 cm depth of field. This means that users have freedom of position as 1.5 m and natural movement of a standing user can be covered.