! $Id: 4270,v 4.1 1994/07/27 14:25:14 pepsa Exp $ coverpage: title_1: WFPC2 COARSE FOCUS proposal_for: SMC/WF2 pi_fname: CHRIS pi_lname: BURROWS pi_inst: ST SCI pi_country: USA pi_phone: 410-338-4913 num_pri: 1 wf_pc: Y realtime: Y ! end of coverpage abstract: line_1: This activity will establish the optimum OTA focus for WFPC2 line_2: imaging. ! ! end of abstract general_form_proposers: lname: BURROWS fname: CHRIS inst: ST SCI country: USA esa: Y ! ! end of general_form_proposers block general_form_text: question: 2 section: 1 line_1: This is the WFPC 2 Coarse Focus. ! question: 3 section: 1 line_1: Description: line_3: A sequence of images is taken with the OTA secondary mirror moved to 5 line_4: positions centered around the initial setting for the servicing mission line_5: (or possibly the adjusted position resulting from the contingency move line_6: in ALI-01). The WFPC2 pick-off mirror adjustment (to fix center of line_7: grid) is done by PSTOL after ALI-02. The PSTOL OTA refocus moves will line_8: each be 9 microns away from the primary mirror after an initial offset line_9: of 27 microns in the opposite direction. Thus there are two moves line_10: (e.g., -27 microns then +9 microns) before the first observation. The line_11: images are of a bright star in NGC188 at the center of the PC with gain line_12: 15 e/DN. The exposure sequence consists of a 0.023 x 0.023 arcsec line_13: raster scan parallel to the CCD pixel orientations of four images each line_14: of 1 sec in F555W so that the image is exposed to at worst a predicted line_15: 1/2 ADC range (for a perfectly centered image which has 40% of the light line_16: in the central pixel). The expsosure time represents a compromise line_17: between jitter and shutter image problems. An additional single 1 sec line_18: exposure through F814W completes the sequence. F814W is better sampled line_19: by the PC camera but less sensitive to misalignments. All four chips line_20: should be read out after each exposure. The telemetry format must be line_21: T or A in order to obtain the forward light shield temperature, and line_22: allow corrections for breathing to be applied. ! question: 5 section: 1 line_1: Prerequisites: line_2: 1) CCDs at -22C or lower, TEC power can be off (temp initially line_3: set in prop 4711). line_4: 2) WFPC2 Aperture Check and Coarse POM Adjustment complete line_5: and POM position set via prop 4333 (WFII-ALI-02). line_7: Things that follow: line_8: COSTAR DOB focus activity (prop 4931) should also wait until the line_9: secondary mirror position is set. line_11: Duration: line_13: 5 orbits + 72 hours think time before dependent operations. ! question: 7 section: 1 line_1: Results: line_3: OTA secondary mirror refocussing move. line_4: Initial actuated fold mirror positions for ALI-04 line_6: Comments: line_8: A focus offset may be applied to the results from this test in PC1 to line_9: allow for the focus differences between the cameras. These differences line_10: can be checked using background stars visible in the other chips. ! !end of general form text general_form_address: lname: BURROWS fname: CHRIS category: PI inst: ST SCI addr_1: 3700 SAN MARTIN DRIVE city: BALTIMORE state: MD zip: 21218 country: USA phone: 410-338-4913 ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: NGC188-686 descr_1: J,704 pos_1: RA=00H 41M 56.125S +/- 0.0044S, pos_2: DEC=+84D 56' 52.995" +/- 0.0058S equinox: 1950 pos_epoch_bj: B pos_epoch_yr: 1963.71 fluxnum_1: 1 fluxval_1: V = 12.33 +/- 0.1 fluxnum_2: 1 fluxval_2: B-V = 1.24 +/- 0.1 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 sequence_1: DEFINE sequence_2: CHECK targname: NGC188-686 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W num_exp: 1 time_per_exp: 1S priority: 1 param_1: ATD-GAIN = 15, param_2: SCAN-READ = ALL, req_1: SPATIAL SCAN; req_2: SEQ 1-3 NO GAP; ! linenum: 2.000 sequence_1: DEFINE sequence_2: CHECK targname: NGC188-686 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F814W num_exp: 1 time_per_exp: 1S priority: 1 param_1: ATD-GAIN = 15 ! linenum: 3.000 sequence_1: DEFINE sequence_2: CHECK targname: DARK config: S/C opmode: DATA aperture: NONE num_exp: 1 time_per_exp: 20M priority: 1 req_1: REQ UPLINK; req_2: RT ANALYSIS; comment_1: UPLINK FOR SM ADJUSTMENT. comment_2: PSTOL = ACTUATOR. ! linenum: 9.000 targname: DARK config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: DEF num_exp: 3 time_per_exp: 1S priority: 1 param_1: ATD-GAIN = 15 req_1: SEQ 9-71 NO GAP; req_2: CYCLE 4/9-100; ! linenum: 10.000 sequence_1: USE sequence_2: CHECK ! linenum: 20.000 sequence_1: USE sequence_2: CHECK ! linenum: 30.000 sequence_1: USE sequence_2: CHECK ! linenum: 40.000 sequence_1: USE sequence_2: CHECK ! linenum: 50.000 sequence_1: USE sequence_2: CHECK ! linenum: 60.000 sequence_1: USE sequence_2: CHECK ! linenum: 70.000 targname: NGC188-686 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W num_exp: 1 time_per_exp: 1S priority: 1 param_1: ATD-GAIN = 15, param_2: SCAN-READ = ALL, req_1: SPATIAL SCAN; ! linenum: 71.000 targname: NGC188-686 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F814W num_exp: 1 time_per_exp: 1S priority: 1 param_1: ATD-GAIN = 15 ! linenum: 100.000 targname: DARK config: S/C opmode: DATA aperture: NONE num_exp: 1 time_per_exp: 20M priority: 1 req_1: REQ UPLINK; req_2: RT ANALYSIS; req_3: AFTER 71 BY 4D +/- 1D; comment_1: UPLINK FOR DETERMINED SM ADJUSTMENT. comment_2: PSTOL = ACTUATOR. ! ! end of exposure logsheet scan_data: line_list: 1.0,70.0 fgs_scan: cont_dwell: D dwell_pnts: 2 dwell_secs: 1.00 scan_width: 0.0230 scan_length: 0.0230 sides_angle: 90.0000 number_lines: 2 scan_rate: 0.0000 first_line_pa: 270.0000 scan_frame: S/C len_offset: 0.0115 wid_offset: 0.0115 ! ! end of scan data