How are digital camera images compressed and brought down from orbit?
Ever since the implementation of the Kodak DCS460 on Shuttle and Station, the majority of digital photographs have been downlinked while the crew is still in orbit via the Ku-band. Images can also be downloaded from the cameras and brought down on a laptop memory card. Most images come down in a Kodak proprietary format (KDK) and are archived by NASA. The files are then extracted and converted into jpgs for web-based browsing and distribution and posted on our website. We post a full resolution (full size) version, and a reduced resolution (small size) jpg. The jpg parameters used are relatively lossy, so there can be some degradation of the image that is visible to the naked eye, however the full-resolution jpgs are still generally suited to print publication or online display without obvious effects. There are a handful of exceptions where crews downlinked jpgs made on orbit before Ku-band was active on ISS, or where other cameras and formats have been used. We often work with scient
