by Bill Anderton
Without the original raw recording from the slow-scan Lunar Surface Camera as downlinked, once hope was lost that they were saved and could be found, NASA began an exercise to collect the best versions that were still available from the post-conversion video and begin a technical restoral process to improve them as much as possible without distorting their historic value.
There were two areas of degradation the restoral process looked to improve upon:
To start, the idea was to use the best available source material. To this end NASA reviewed:
It was found that the quality of each source varied from source to source as well as from time segment to time segment.
The slow scan converter and its optical transfer process were sources of much of the signal degradation in the process simply due the low level of the state of the art of the period. While precise in its tolerances and a finely-calibrated piece of broadcast gear, the scan converter was greatly limited by the technology of its time. They needed something more advanced than pointing an NTSC camera at the screen of a monitor showing the slow scan video. The approach was limited by the technology of its time.
Also, there were other issues as well. In 2004, after a careful review of the archived video sources, it was discovered that the Goldstone Slow Scan Converter’s internal CRT was set at an improper level that compressed the dim shadows into black. The other two scan converters were set properly.
The restoration team assembled the best remain version of each segment of the moon walk to serve as the input into the technical restoral process. Each "best-of-breed" segment was digitized and served as the input for the restoral process.
Then, Lowry Digital of Burbank, California was tapped to enhance the video footage. Lowery Digital has lots of Hollywood experience restoring theatrical movies. They also have developed powerful image processing software and techniques for these types of restoral projects.
According to an NPR piece, "Lowry says more than a hundred computers processed the images, carefully removing things like random noise and camera shake, without destroying the images' historical legitimacy."
NASA release the restored video of the entire moon walk in December 2009. The restoration project cost $230,000.
NASA's video restoration project was one of the sources used by the MoonScape documentary team; along with rescans of the 16mm film and 70mm stills. The MoonScape team purchased an entire set of restored videos to use in the documentary.