IRAS Explanatory Supplement
XII. Errata and Revisions as of 1987
B. Total Intensity Data
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B.1 Total Intensity MapsA number of fields were omitted from the first release of the third HCON sky images due to the misapplication of a calibration factor (Section XI.F). This error has been corrected and the second release of the third HCON includes all the possible fields.
B.2. Version 2.0 of the Zodiacal Observation History File
The Zodiacal Observation History File (ZOHF) was recreated to correct a ½° in-scan position error found in Version 1.0. Several additional improvements were incorporated at the same time. A calibration correction that partially adjusts for errors in the electronic baseline was added. The sampling interval was decreased to 4 seconds of time (~ ¼°) from 8 seconds of time (~ ½°). The 8 second (~ ½°) boxcar filter size remains the same. All records in Version 2.0 represent 8 seconds of contiguous data, whereas in Version 1.0, non-contiguous data were incorporated in the file when possible. Data from the edge detectors were not used in the new file. This means the average values represent, in cross-san, 27.3' for the 12 µm wavelength band and 28.5' for the 60 µm wavelength band. Though data from edge detectors in the 25 and 100 µm bands were also removed, the remaining full-sized detectors in these bands cover the full 30' width of the focal plane.