Astronomical Image Acquisition Using an Improved Track and Accumulate Method

“Track and Accumulate” (T&A) is an alternative astronomical image capture method where exposures are combined during imaging by aligning on a reference star. The benefit is an increased dynamic range, thus allowing both bright and dim objects to be captured in the same image. The main limitation is that correlated noise from the frames will form squiggles on the combined image as the result of telescope drift, especially when using narrowband filters. In general, the advantages of the T&A method are insufficient to outweigh this limitation, and most astrophotographers prefer to take individual images and combine later. In this paper, several enhancements to the original T&A method are detailed, which improve on the process as well as reduce correlated noise. An algorithm is proposed where most postprocessing is integrated into the T&A procedure. These improvements simplify the imaging process, reduce hardware costs, and lower the technical bar for producing quality astronomical photos. The algorithm has been field tested on a variety of astronomical objects, and the resultant images are as good as those produced by the traditional method, yet require less imaging and processing time.