WF/PC-I Science Filters

• Proposal for handling and initial characterizations of returned WF/PC-I optical filters was distributed in July 1994 (J. Trauger memo, 7/9/94), and amended to include testing of one additional filter (J. MacKentry memo).
• All proposed initial characterizations have been completed at JPL. The filters remain in dry N2 purge in JPL bonded stores.
• Filter passband and blocking curves are now available in digital files available over the Internet. These have been made available to the STScI and the WF/PC-I and WF/PC-II science teams.
• Further work will be carried out as required in response to specific requests.

• The WF/PC-I optical filters came to JPL installed in the SOFA mechanism, and under nitrogen purge.
• SOFA wheels were removed from the SOFA housing at Schaeffer Magnetics, in a manner minimizing exposure of the mechanism and filters to air and humidity.
• Filters were removed from the SOFA wheels by an experienced JPL technician familiar with the handling of optical filters and the SOFA mechanism.
• Prior to removing the filters from the SOFA wheels, the JPL technician inspected the filters visually, and noted the orientation of the filter in the wheel.
• Filters were visually inspected following removal and immediately placed in a nitrogen-purged storage container which protects the filters from physical change.
• A selected subset of filters was initially characterized at JPL for the spectral profile of the passband at five positions (filter center and center of the four sides) and in the blocking band (logarithmic scale accurate to 10^-6), in the same manner as the WF/PC-II filters.
• This filter subset includes narrowband filters F673N, F658N, F656N, F664N, F631N, F502N, F588N, F469N, F517N and F1042N.
• Also the photometric filters F336W, F439W, F555W, F675W and F791W.
• The filters are now in nitrogen-purged storage, and preserved for further testing by the WF/PC-I and/or WF/PC-II science teams.