Warren A. Keller is a world-renowned astro-imager (APOD, Sky & Telescope, Astronomy magazines, etc.) and teacher of image processing. He has presented at the Northeast, Midwest, and Advanced Imaging Conferences and has written extensively on the subject. He is a six-time Sky & Telescope author. Keller produced the definitive commercial video tutorial series for PixInsight and published the first edition of Inside PixInsight with Springer in 2016.

PixInsight has taken the astro-imaging world by storm. As the first comprehensive postprocessing platform to be created by astro-imagers for astro-imagers, it has for many replaced other generic graphics editors as the software of choice. PixInsight has been embraced by professionals such as the James Webb (and Hubble) Space Telescope's science imager Joseph DePasquale and Calar Alto's Vicent Peris, as well as thousands of amateurs around the world.