App Description

App Site Link

Runs on Windows / Linux / macOS

Version

Checked
AstroImageJ - ImageJ enhanced for Astronomy https://www.astro.louisville.edu/software/astroimagej/ W / L / m 3.4.0.01 11/3/2020
DARKTABLE is similar to Adobe Lightroom, it is cataloging and library sorting software. https://www.darktable.org W / L / m 3.0.2 23/6/2020
DeepSkyStacker is a¬†freeware¬†for astrophotographers that simplifies all the pre-processing steps of deep sky pictures. http://deepskystacker.free.fr/english/index.html W   23/6/2020
FITS Liberator Image Processing

https://www.spacetelescope.org/projects/fits_liberator/

http://fits.gsfc.nasa.gov/fits_home.html

W / m  3 9/3/2020
Gimp http://www.gimp.org W / L / m 2.10.18 10/3/2020
Heasarc http://heasarc.gsfc.nasa.gov/ftools/fv/ W / L / m 5.5 10/3/2020
ImageJ 64 image processing https://imagej.nih.gov/ij/index.html W / L / m  1.52t 9/3/2020
ImageJ 64 Help ImageJ Help W / L / m   9/3/2020
Inkscape - handles .svg format files  http://www.inkscape.org/en/  W / L / m  0.92  9/3/2020
Lynkeos - image stacking  http://lynkeos.sourceforge.net  macOS  3.3  9/3/2020
NASAView https://pds.nasa.gov/tools/about/pds3-tools/nasa-view.shtml W / L / m 3.18.0 10/3/2020
SAOImage DS9 is an astronomical imaging and data visualization application.  http://ds9.si.edu/site/Home.html  W / L / m  8.1  3/3/2020
         

Summary on Graphics for web
The key to optimizing web graphics is to minimize their size, number, and quality, and maximize cropping. 
Combine adjacent images and use client-side imagemaps instead. Substitute CSS-based rollovers for bandwidth-hungry image-based rollovers. 
Replace graphic text with styled text. Finally, to minimize HTTP requests, reuse images with the same URL. 
With all graphics, you can't go wrong if you do the following:

Eliminate and combine your images to minimize HTTP requests.
Convert graphic text into styled text.
Maximize cropping and minimize dimensions.
Use the right image format (JPEGs for photographs).
Use interlacing with care (avoid interlacing on smaller images and most PNGs).
When capturing photographs, use a stable platform, (tripod, image stabilization)
Minimize noise, smear, and complexity.
Use weighted optimization to reduce less important areas and blur backgrounds (for JPEGs).
Minimize colors (bit-depth) for palette-based formats.
Use a high-quality quantizer on true-color originals and limit dithering.
Set your image resolution to 72dpi.
Specify the actual height and width of all images.
Use grayscale where possible.
Use thumbnails linked to larger images.
Experiment with different settings and programs.
Resources for images and image processing.

Image resources for both complete images and raw data which can be processed in applications like GIMP to produce final 'colour' (or false colour images). Most NASA images are in the public domain unless otherwise stated, however if used credit should be given.

ESO images and videos, along with the texts of press releases, announcements, pictures of the week and captions, are released under the Creative Commons Attribution 3.0 Unported license and may on a non-exclusive basis be reproduced without fee provided they are clearly and visibly credited. See ESO site for more details http://www.eso.org/public/outreach/copyright.html


Resources for images and image processing Site Link
Space Telescope image examples http://www.spacetelescope.org/projects/fits_liberator/eagledata/
Space Telescope image examples http://www.spacetelescope.org/projects/fits_liberator/datasets/
Space Telescope heritage image examples http://archive.stsci.edu/prepds/heritage/
Space Telescope image examples M51 http://archive.stsci.edu/prepds/m51/datalist.html
Astrobits http://www.noao.edu/education/astrobits/course-outline.php
Hubble http://www.spacetelescope.org/projects/hiddentreasures/
Hubble http://hubblesite.org/gallery/album/entire/
Chandra http://chandra.si.edu/photo/openFITS/casa.html
Lucky Imaging http://www.ast.cam.ac.uk/ ...lucky.imaging