Nebulosity
Nebulosity (Windows and OS X) is designed to be a powerful, but simple to use capture and processing application for a wide range of astronomy CCD cameras. Many cameras are supported for capture (see below) and images from just about anything can be processed (support for many FITS formats, PNG, TIFF, JPEG, CR2/CRW, etc). Its goal is to suit people ranging from the novice imager who wants to create his or her first images to the advanced imager who wants a convenient, flexible capture application for use in the field. In it, you get a host of purpose-built powerful tools to make the most out of your images (e.g., Digital Development Processing, traditional alignment/stacking (equatorial and alt-az), Drizzle alignment/stacking, Bad Pixel Mapping, LRGB tools, real-time tricolor histograms for color balancing, star tightening via edge detection, adaptive scaling of stacks, Canon CR2/CRW RAW Bayer matrix loading, 32/96-bit accuracy, etc.)
http://www.stark-labs.com/nebulosity.html - Details

RegiStar
RegiStar is an image alignment, or registration, program that was designed to work specifically with astronomical images.
http://www.aurigaimaging.com/ - Details

ImageTool
UTHSCSA ImageTool (IT) is a free image processing and analysis program for Microsoft Windows 9x, Windows ME or Windows NT. IT can acquire, display, edit, analyze, process, compress, save and print gray scale and color images.IT can read and write over 22 common file formats including BMP, PCX, TIF, GIF and JPEG. Image analysis functions include dimensional (distance, angle, perimeter, area) and gray scale measurements
http://ddsdx.uthscsa.edu/dig/itdesc.html - Details

Deep Sky Colors - Astrophotography by Rogelio Bernal Andreo
Astronomical photography, Digital Astrophotography tips and techniques
http://blog.deepskycolors.com/tools.html - Details

GuideDog
Standalone Autoguiding for Webcams Dedicated, standalone, easy-to-use autoguider software Supports the SC-1 long-exposure webcam to allow guiding on faint stars Uses ASCOM for scope control to support many different telescopes/mounts Support for parallel port based relay boxes to connect to the CCD Guide Port of most mounts Sub-pixel guiding on a star centroid Audible alarm if lock on the guide star is lost
http://www.barkosoftware.com/GuideDog/ - Details

CADET
CADET is basically a program for calibration and deconvolution of astronomical images in FITS, BMP and JPEG formats. See a
http://www.terra.es/personal2/oscarcj/introeng.htm - Details

PHD Guiding
PHD Guiding is designed to be "Push Here Dummy" simple, yet provide powerful, intelligent auto-guiding of your telescope for both PCs and Macs. Connect your mount, your camera, select a star, and start guiding. That's it! In PHD Guiding, all calibration is taken care of automatically. You do not need to tell it anything about the orientation of your camera, nor do you need to tell it anything about the image scale.
http://www.stark-labs.com/phdguiding.html - Details

AviRaw
AviRaw allows opening of an AVI and preview as ordinary RGB (decoded via codec as usual) preview as RAW luminosity (Y channel only) from ordinary or RAW captures preview as RAW colour, debayerized from Y channel (works only for RAW captures) save as new AVI using the selected mode (starting V2.3 this works also for Win9x) save as new BMPs (1 per frame) using the selected mode properly handle dropped frames for preview and save (dropped frames are not checked)
http://arnholm.org/astro/software/aviraw/ - Details

Imagen - CCDC
Imagen is image acquisition software for old Starlight Xpress CCD cameras.
http://www.astroshed.com/imagen/imagen.htm - Details

Cadet
Image processing program, with special focus on astronomical image processing. It includes calibration, deconvolution (Maximum Entropy and Richardson-Lucy), Dr. Okano's Digital Development Process, colour combine, unsharp mask and many more!
http://www.terra.es/personal2/oscarcj/ - Details

DeepSkyStacker
DeepSkyStacker is a freeware for astrophotographers that simplifies all the pre-processing steps of deep sky pictures and is specialized in RAW files from DSLRs.
http://deepskystacker.free.fr/ - Details

AstroAlign 2.0
AstroAlign is a software program for unconventional (?) image processing of astronomical and other images. The program is free and may be used by anyone who finds it useful. However, read the disclaimer at the bottom of this page before you start using it.
http://www.arnholm.org/astro/software/astroalign/AstroAlign.htm - Details

DSLR Timer
DSLR Timer is a Freeware DSLR Interval Timer using the parallel port or serial port of your notepad or PC. It can control series of long exposures of digital cameras as it is needed for astrophotography. For astrophotos it is usual to have series of exposures with 2 to 5 minutes exposure time. DSLR Timer is the convenient tool to control this for you. I use it with Pentax *ist DS and Canon EOS 20D. It should work also with other cameras.
http://home.arcor.de/th.bach/Software/Software2En.htm - Details

AstroMB
is a powerful, fast and reliable way to manage your astronomical images and catalogs. It is especially useful for comparing astronomical images taken at different wavelengths, or at different times, and to match them with astronomical catalogs.
http://www.astromb.com/ - Details

Astro-Snap
Astro-Snap allows you to take astronomical pictures at low cost with a WEBCAM Simple image acquisition or real time frame integration (standard or loop frame integration). - Real time planetary video processing (at capture time) - Long exposure acquisition with the following cameras (modified following Steve Chambers' design) : Philips Vesta-SC, Toucam-SC, Quickcam Pro3000-SC. - Image resolution up to 800x600 - Focusing aid based on a star's apparent size (FWHM), along with sound indicator for remote tuning - Focusing aid on complex objects,along with a sound indicator for remote tuning - Image stabilization and automatic tracking of the object in the camera's field of view. - Automatic Dark or Flat-Field processing - Can let you make pseudo long exposures without tracking needed. - Automatic image selection based on each frame's quality (planetary imaging). - Manual or automatic saving of bitmaps. - Very fast and precise Polar aligning aid using two popular drift align methods : Bigourdan and King.
http://www.astrosnap.com/ - Details

PinPoint Astrometric Engine 5.0
Welcome to the web site for the PinPoint Astrometric Engine, a programmable engine that provides sensitive, robust, high-speed research-grade astrometric image processing for FITS files from any camera. A set of point-and-click tools (Visual PinPoint) for fast mass plate solving and survey-level asteroid and supernova hunting are included.
http://pinpoint.dc3.com/ - Details

Avis
Avis (Astro-vis) is a freeware FITS viewer for Windows 95, 98, 2000 and XP FITS files are used in scientific applications like astronomy and medical imaging. * Opens FITS files: (8 & 16 bit), supports multiple file opening and drag & drop from Explorer and other Windows shells. * Imports CCD files: like SBIG ST8, ST7, ST6, ST5, ST4, Starlight, Hisis, Pixcell and others. Imports graytones TIFF and TGA files. * Saves FITS and allows modifications of the FITS Header. * Exports files: as TXT format, RAW, TIF, TGA, BMP and JPEG. * On-line help: full documentation about Avis and about FITS file format.
http://www.sira.it/msb/avis.htm - Details

Fits4Win
A Windows Suite for viewing and inspecting FITS files from Explorer. Fits4Win supports 8, 16 and 32-bit integer and floating-point, mono and RGB FITS files under Windows 2000, XP and 98
http://astroshed.com/fits4win/fits4win.html - Details

Astroart 4.0
A complete software for image processing, photometry, astrometry, CCD control and image stacking for CCD and film images.
http://www.msb-astroart.com/ - Details

RC-Astro Processing Console
This is a program that provides some new image processing functions to MaxIm.
http://www.rc-astro.com/resources/rc_console.html - Details

FitsPlug
FITS plugin for Adobe Photoshop V5+ for Windows. FITS is a file format originally defined by the International Astronomical Union (IAU) to store and interchange astronomical data between scientific organizations;
http://astroshed.com/fitsplug/fitsplug.html - Details