Overview Work began in early 2012 as the Mango Open Movie Project. The film is a combination of live-action and computer generated sets, props and special effects. It was officially released online for viewing and download on September 26, 2012. Following Elephants Dream, Big Buck Bunny, Yo Frankie and Sintel, the short movie is the fifth project from the Blender Foundation. Tears of Steel was created by the Blender Institute, a division of the foundation set up specifically to facilitate the creation of open content films and games. The film was funded by the Blender Foundation, donations from the Blender community, pre-sales of the film's DVD, the Netherlands Film Fund and Cinegrid Amsterdam. The film itself and any material made in the studio are released under the Creative Commons Attribution License. Plot The short science fiction film is about a group of warriors and scientists who gather at the “Oude Kerk” in a future Amsterdam to stage a crucial event from the past in a desperate attempt to rescue the world from destructive robots. Technical information The live-action footage was filmed digitally using a Sony F65 Cinealta digital motion picture camera. The finished film is available for viewing and download in 4K and HD resolutions, Dolby 5.1 audio and 2.35:1 aspect ratio format. Filming was done in Amsterdam, the Netherlands. All visual effects, computer generated content and compositing work was done within the Blender software package. The Mango Open Movie Channel on YouTube contains several videos explaining development and the techniques used by the team in making the film. On March 15, 2013, the computer-based film makers released the source material (about 5 times the length of the used materials) into the public using the CC-by license with the major restriction that images of the actors shall not be used for commercials. The material is available using the OpenEXR half float file encoding and makes up 4 TB of data for roughly 80,000 frames using a dimension of 4096 × 2160 pixels (see also Ultra HD). It is the intention of the releasers to ease future developments for the film industry and other areas of image processing by making available this noticeable large amount of high definition professionally shot test data that has not been seen until now. Improvements to Blender As with the previous Blender Open Movie Projects, the Blender developers and community worked together to provide a movie studio style production work flow for the team. The results are a complete open source pipeline for visual effects work in Blender including but not limited to camera tracking, rotoscoping, compositing and color grading. These features are available with Blender v. 2.64. Reception The reviewer David Masters praised the film's visual effects while noting that the acting was wooden in places.