The Kodak DCS 760c made its debut in November of 2001 when it boarded the Shuttle Endeavour.
The 6.3 megapixel digital camera would replace NASA's short lived affair with the Kodak DCS 660 camera which had previously flown on missions earlier that same year.
The DCS 660 when released, carried a high ticket price. According to my records, NASA acquired the DCS 660 cameras for $25495 while the the DCS 760 had an acquisition cost of one quarter that: $6295.
Aside from the hefty savings to the tax payer, the DCS 760 also carried improvements including:
- ISO settings ranging from 80-400 (80-200 on the DCS 660)
- increased burst rate of 1.5 fps with a 128 MB buffer that permitted up to 24 sequential images shooting (1 fps with maximum 3 frames write-capable on the DCS 660)
- Built-in standard IR Reduction filter (as opposed to a Lithium Niobate Anti-Aliasing filter for DCS 660)
- Video out: NTSC or PAL (not on the DCS 660)
- Larger LCD screen with higher resolution
The Kodak DCS 760 used a Nikon F5 body for image capture. The F5 film camera was already in active use in space, so adopting the DCS 760 also meant for a shorter learning curve to get the astronauts familiar with the gear operation.
The Kodak DCS 760 was well received by NASA and regularly flew from late 2001 through 2008. The camera would serve multiple duties over its career including intra vehicular activity (IVA) aboard the space station and the shuttle (recording astronaut duties, experiments, shuttle and ISS observations, mapping, earth observations), as well as extra vehicular activity (EVA) during spacewalks and launch recording and separation.
After the loss of the Shuttle Columbia (mission STS-107) in February of 2003, the most important duty for the camera was to photograph Shuttle launch damage while the orbiter was still in space.
Once the Shuttle arrived at the International Space Station, the pilot would perform a rendezvous pitch maneuver, basically a back flip of the shuttle, so it could expose its heat shield to the astronauts on the station. The astronauts, equipped with 400mm and 800mm Nikkor lenses mounted on the DCS 760, would be able to capture damage as small as 1 inch from a distance of 600 feet. The images were then downlinked via the Tracking and Data Relay Satellite System for closer inspection on Earth. Previously, NASA had to rely on terrestrial and airborne tracking camera footage, which was shot on film and, coupled with the distance, had relatively low resolution.
The DCS 760 featured a Firewire interface which was a dramatic improvement in the speed of downlinking images over the older DCS 460's SCSI cable connection, so the DCS 760 would also take over duties as the camera responsible for EarthKam.
What makes a NASA modified Kodak DCS 760 camera different than a regular consumer model?
Like its predecessor models, the DCS 660 and DCS 460, the version NASA used of the DCS 760 was almost identical to the commercially available camera with a few minor exceptions:
- Internal lubricants were formulated to NASA specifications so that they could withstand the rigors of space.
- Decals were applied to indicate the NASA Part (PN) and Serial (SN) numbers, as well as for the MIC (microphone) and the input for the DC Power Adapter
- Velcro was applied, usually on the side of the camera opposite the grip and occasionally on the baseplate. Velcro is used to keep things in place easily in a zero gravity environment. Blue Velcro was applied to most of the cameras, however I have an EVA modified body that uses White velcro.
- To enable bracket mounting or on multi-positional arms, the camera would usually be fitted with a quick release type plate on the base.
- Covers were removed for the Firewire and remote connections as well as for the DC power adapter
- Minor modifications were made to the firmware, such as:
-- changing the requirement for user acknowledgement when an ERROR was encountered, before allowing the next image to be captured
-- if the camera detected an 'out of temperature range' condition, the camera would still allow for image capture
For the DCS 760 cameras that were intended to be used outside of the spacecraft out in the vacuum of space, additional modifications were required:
Firstly, the lubricants and adhesives needed to be able to withstand temperatures ranges of -50 degrees celsius upward to 110 degrees.
In these huge temperature swings, the camera itself needed to be insulated. This was accomplished with a thermal blanket; in essence a 'coat' for the camera. While I have not found specific specifications for the DCS 760's thermal blanket, I assume that it followed a similar construction to earlier thermal blankets for the EVA cameras, which involved a construction similar to the spacesuits: 12 layers of aluminized mylar film with a shell of Ortho fabric on the outside and Teflon fabric on the inside.
The DCS 760 has a LED lamp directly to the right of the video input next to where the memory cards are inserted. The LED lamp flashes whenever the camera is busy writing to or accessing the card. This lamp can only be seen when the door covering the compartment is open.
When an astronaut is on EVA, the camera is wrapped in a thermal blanket and this prevents access to this compartment. Engineers had to develop a solution to enable the astronauts to see this LED lamp with the door closed and the camera completely wrapped in the thermal blanket insulation. Their solution was this:
The compartment door had a hole drilled through it which was in perfect alignment with the LAMP. A rubber gasket was then applied to both the outside and inside of the door around the hole.
A long translucent rubber tube, referred to as a 'light-tube' was then inserted through this hole in the door and then into the recess surrounding the LED lamp. A hole in the thermal blanket would allow the end of the light tube to emerge, thus allowing the astronauts to see the 'busy' lamp when the camera was 'fully dressed'.
This modification to the memory card compartment was one of a few modifications made for the specific DCS 760 cameras that would be designated for EVA use.
Another modification that was made to the EVA version was to remove the strap lugs from the camera. A neck strap and wrist strap were not necessary in deep space, so the commercial lugs were milled off
During STS-116, astronaut Suni Williams was performing the mission's second of three spacewalks when the screw (securing the camera's mounting plate to their spacesuit) backed out. The plate released from the suit, with the camera attached, and the camera floated off into the universe.
This tragic loss of the camera led Engineers to use a dental epoxy known as Dycal to apply to the screw to keep it in place. In addition a tether was also added to the thermal blanket
The EVA modified versions of the DCS 760 also tended to sport white decals with black lettering as opposed to the IVA versions which had black decals with white lettering