A motor controlled rail assembly is provided which simplifies and automates the process of taking focus-stacked pictures. This device can be used to incrementally move a camera or other photographic device a programmable distance forward or backward in precise steps relative to an external object to facilitate focus-stacked photography. The device may include a motor-driven macro rail assembly, a controller assembly and a camera, which, generally speaking, are configured as follows: a camera is attached to a macro rail carriage which is driven by the motor and controller. The device may have different modes of operation (an automatic step mode, an automatic distance mode, a total distance mode, a distance per step mode, a continuous mode and a manual mode) to yield improved results in different situations.