\header ENTRY_TIME = 2000 MAY 03 23:25:16 SYSTEM_NAME = NAVCAM AUTHOR = RAY L. NEWBURN, JR. INSTITUTION = JET PROPULSION LABORATORY START_TIME = 1999 MAR 19 01:44:46 STOP_TIME = NULL TARGET = STAR DAY = NULL \text A series of 27 images was planned, the first to be taken with the STARDUST navigation camera. There were to be three sets of images, each consisting of an image through each of the eight filters plus a bias (zero exposure) frame. The first set had the calibration lamp turned on and compression off. After the first three frames, a bias frame plus 100 ms exposures through the C2 and yellow filters, the spacecraft "safed itself." Nothing could be detected on either frame. The two filters used were quite narrow, 12 and 4 nm wide at the half peak transmission points, but the central star was of 2nd magnitude, so this was a bit worrisome. We could not be sure we were pointed in the correct direction, since no geometric calibration had been carried out, so we simply planned to take longer exposures as soon as possible. Calibration lamp exposures in the calibration lab for the two filters were of 20 second duration, so it was not too troubling that the background level was not significantly higher than in the bias frame. In fact the software changes required to assure successful imaging without causing spacecraft problems took seven months to develope, so further images were not acquired until October. \header ENTRY_TIME = 2000 MAY 04 01:04:07 SYSTEM_NAME = NAVCAM AUTHOR = RAY L. NEWBURN, JR. INSTITUTION = JET PROPULSION LABORATORY START_TIME = 1999 OCT 21 14:17:46 STOP_TIME = 1999 OCT 21 14:20:56 TARGET = STAR DAY = NULL \text With the spacecraft software now working properly, a series of nine images were acquired, one bias frame and one image through each of the eight filters. The images were returned to the ground a month later when STARDUST had a block of 70m DSN time, the spacecraft now being more than two AU from Earth. This time the calibration lamp was off, as was the compression, and an exposure time of 500 ms was set. The brightest star in the field was Omicron Ophiuchus,a double star with 10.2 arcsec separation and V magnitudes of 5.20 and 6.80. Ab Initio calculations indicated that these together SHOULD have given a signal of about 3700 dn in the OpNav filter. The sum of the two brightest pixels was only 43 dn. Allowing for some smear and some spread (the OpNav filter has a point spread of about two pixels), the 10 pixels surrounding these two add 64 dn, for a total of 107, indicating the signal to be more spread than expected and some 30 - 40 times weaker. Omicron Ophiuchus was also found on the HiRes filter, which has a point spread less than half a pixel, the 12 pixel area having a total of 88 dn. It was not seen on any of the narrow filters. The motion during the 25 seconds between the exposures was 25 pixels, the amount expected and in the correct direction for the spacecraft drift rate. One other star, the second brightest in the field and of magnitude 6.7, was found in the correct location on the OpNav filter. At this point it was obvious that either we were not getting the correct exposure times or that some form of contamination was decreasing the signal strength. We hoped that it was some form of correctable software problem. While this possibility was being studied, the decision was made that the next images should be taken of the calibration lamp through the OpNav filter to determine whether we were getting the correct exposures.