Software – Freeware
The Photographer’s Ephemeris (TPE) helps you plan outdoor photography shoots in natural light, particularly landscape and urban scenes. It’s a map-centric sun and moon calculator: see how the light will fall on the land, day or night, for any location on earth. TPE for Desktop is the original – and free – version of the program, and is the premier outdoor photography planning tool used by thousands of photographers, amateur and professional, around the world.
GIMP is an acronym for GNU Image Manipulation Program. It is a freely distributed program for such tasks as photo retouching, image composition and image authoring. It has many capabilities. It can be used as a simple paint program, an expert quality photo retouching program, an online batch processing system, a mass production image renderer, an image format converter, etc. GIMP is expandable and extensible. It is designed to be augmented with plug-ins and extensions to do just about anything. The advanced scripting interface allows everything from the simplest task to the most complex image manipulation procedures to be easily scripted.
via GIMP – Introduction.
Please donate if you do decide to use open source, it’s a worthy cause.