This is the user forum for AstroImageJ. Bug reports, help requests, comments, and feature requests should be posted here. AstroImageJ is open source software and is distributed under the terms of the GNU General Public License. AstroImageJ is a Java image processing program based on ImageJ from the NIH. Downloadable distributions are available for Windows, Mac OS, and Linux. The ImageJ user forum at http://forum.imagej.net/ should be consulted for base ImageJ issues. If you use AstroImageJ in your work, please reference the AstroImageJ Astronomical Journal open access paper Collins, Kielkopf, Stassun, and Hessman 2017, AJ, 153, 77. An expanded edition of the paper is available that provides more detailed descriptions of the AIJ user interface. The primary AstroImageJ development team includes Karen Collins (Smithsonian Astrophysical Observatory), Kevin Eastridge (George Mason University), and John Kielkopf (University of Louisville). The AstroImageJ project would like to extend a special thanks to Eric Jensen (Swarthmore), Dennis Conti (AAVSO), Brian Hill (Saint Mary's College of California), and Matthew Craig (Minnesota State University Moorhead) for their important contributions to the development of AstroImageJ.