The Acratech Nodal Rail is a nodal slide, designed to adjust your camera's position front to back, thereby enabling positioning of the nodal point on your lens over the center of rotation. This allows you to create accurate stitched panoramic images. Our nodal rail also features adjustable stops that can be preset to the nodal point of your two favorite focal lengths.
Posted by Bob Trlin on 20th Dec 2015
I use this not as a nodal rail but as a focusing "assist" rail for macros and macro focus stacking. My camera has an in-camera focus bracketing and focus stacking feature so the precision mechanism of the traditional quality focusing rail is no longer required except for the most exacting scientific work. In-camera focus bracketing is done in seconds rather than minutes and in theory, has the perspective advantage of keeping the camera to subject distance constant.