The recent rise of the three-dimensional television (3DTV) industry has led to a wide exploitation of the dual-lens stereoscopic camera. However, when the zoom-in function is used, it is possible that a camera object is magnified only with a fixed convergence point, thereby leading to visual discomfort. In this paper, we propose several methods based on which a convergence point can be adjusted to prevent visual discomfort during zoom-in for a dual-lens stereoscopic camera. Further, we produce 3D contents by applying the proposed methods to certain cases and at certain distances and conduct a subjective evaluation. On the subjective evaluation, 48 subjects watch the 3D contents created by the proposed methods and score the stages of the visual comfort. The result of the subjective evaluation shows that some of the proposed methods are more efficient than the others. We hope that these proposed high-efficiency methods can be applied to produce a dual-lens stereoscopic camera that allows convenient stereoscopic photography.