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6 3. It was difficult to ascertain when a magazine had run out of film. A positive indication was given by the camera firing even though the film had run out, therefore, the camera should not be allowed to fire (R). It is also necessary to have an indication when it is time to change film so that data opportunities are not wasted by taking pictures with no film. The only anomaly that occurred with the Linhoff was a blown fuse which halted camera operations until it was replaced with a readily available spare. Overall, the operation and reliability of the Linhoff system was excellent. Television (TV) System: The control and set up of the television systems appeared nominal for the entire flight. Video tape recorder (VTR) interface, both in record and downlink, performed correctly, but there was a shortage of VTR tapes on board which necessitated recording over all three inflight maintenance (IFM) tapes and recording over other previously recorded data considered of less importance. The VTR requirements for a flight should be monitored and sufficient tapes should be carried to cover all planned VTR activities, and consideration should be given to a VTR with more capacity than 30 minutes per tape (R). The payload bay (PLB) cameras provided less than acceptable performance on this flight. Camera D appreared to "fog over" after day 3 and camera C could not be focussed properly from the beginning of the flight. In addition, the resolution of the television monitor did not allow accurate positioning of payloads in the bay. For example, the Long Duration Exposure Facility (LDEF) trunnion fittings could not be readily seen, nor could the Solar Maximum Satellite be accurately positioned for berthing utilizing the monitors. VTR tapes of these operations show good contrast, and if the monitors had exhibited the same level of contrast, the payload handling would have been much more expeditious and accurate. None of the current simulations portray the lack of TV monitor resolution and better onboard monitors (even color) should be considered for future flights to enhance mission success (R). An additional problem which caused consternation while performing proximity operations and satellite grapple was the automatic lighting control (ALC) function of the television cameras. Just when the crew needed accurate positioning information or a good picture of the grapple fixture to do a rotating grapple, the ALC would start blossoming and darkening cyclicly making it almost impossible to use the TV monitor as an aid. This occurred in the sunlight with variable reflections, but the TV system was unable to handle it. Because of the heavy crew workload during these times and the fact that the Remote Manipulator System (RMS) operator necessarily occupies the space in front of panel A7U, it was impossible to do manual iris corrections. Since the above scenario would be repeated in similar circumstances on future flights, the ALC feature should be modified to eliminate the cyclic over bright ot over dark conditions (R). The in cabin TV system performed nominally for the entire mission with no apparent problems. The extravehicular mobility unit (EMU) television operated nominally during both EVAs. Some interference was noted between the EMU and PBL televisions during EVA 1. This was an expected condition due to system configuration. The Laser Ranging System exhibited several problems during on-orbit operations. The laser on camera B became inoperative on day 2. The laser on camera C could not be turned OFF (starting of day 3) without turning OFF camera C. In addition,
