Subject: [SLR-Mail] No. 429: Florence: Calibration Scheme Topic From: Werner Gurtner ******************************************************************************** SLR Electronic Mail 1999-09-06 10:01:00 UTC Message No. 429 ******************************************************************************** Author: Werner Gurtner Subject: Florence: Calibration Scheme Topic >From gurtner@ubeclu.unibe.chMon Sep 6 09:59:47 1999 Calibration Schemes ******************* COLLOQUIUM ON SLR- SYSTEM CALIBRATION ISSUES 23+24 September 1999 University of Florence, Italy Dear colleagues, the call for participation for the SLR System Calibration Colloqium in Florence stated: ”Since the review and documentation of calibration practices is the major goal for this colloquium all stations are asked to provide input in form of viewgraphs, tables or written procedures, which are discussed during the colloquium. The chairmen are asked to act as moderators, who keep the discussion focused and conclusion orientated.” May I ask the representatives of the laser observatories attending the colloquium to be prepared to discuss the issues of calibration procedures and schemes, ---------------------------------- especially of course with respect to your own system. Below I have listed a few topics that should be addressed during the colloquium. Calibration to external target: ------------------------------- Pre-pass, post-pass, pre- and post pass, interleaved calibration: - Criteria for how often, how long - How to compute actual values to use as range correction (Interpolation in time, filtering, smoothing, etc) - Path length changes in the telescope between target direction and satellite directions Maximum target distance, refraction corrections Calibration to internal target ------------------------------ (Internal being ”within the telescope or laser setup”) - Criteria for how often, how long (extreme: single shot calibration) - How to compute actual values to use as range correction - Surveyed targets (with measured optical path length correction) versus fictitious target within system Internal vs. External --------------------- Where are the major advantages/disadvantages? Do we need both? Some keywords: Azimuth/elevation dependence, check of variations across beam width, flexibility (rapid changes in system delays), satellite-dependent calibration scheme, reliability, all-weather capability Other topics: ------------ - Attenuation of calibration return signal levels to the satellite returns (i.e. satellite-dependent calibration vs. common calibration) - Maintenance and accessibility of calibration history Related Topics: -------------- - Target designs will obviously be dealt with by John Luck ”Target design and Local Survey”. Thank you very much for your cooperation. Best regards Werner Gurtner (Calibration Schemes) From: slrmail (EDC) [Mailed From: WERNER GURTNER ] ********************************************************************************