RegiStax is an image processing tool that is used to stack (digital) astronomical image captures, in order to improve detail, color and overall quality. It uses Fast Fourier Transformation Initial alignment system and offers various controls to adjust brightness, gamma, histogram, RGB shift and much more. Other features include user controlled wavelet filters and schemes, resampling, horizontal and vertical de-interlacing and more.

The license of this software is Freeware, you can free download and free use this digital photo software.