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The EIS Experience: Lessons Learned. May 12, 2005. Background. EIS 1996-2004 Original mission: Limited-term experimental project Preparation of data sets for VLT commissioning and early operation Coordination with ESO community (SWG, visitors) Train & disseminate tools as possible
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The EIS Experience: Lessons Learned May 12, 2005
Background • EIS 1996-2004 • Original mission: • Limited-term experimental project • Preparation of data sets for VLT commissioning and early operation • Coordination with ESO community (SWG, visitors) • Train & disseminate tools as possible • In 1999 mission expanded • Support long-term public surveys (1997-present; 8 years) • Develop infrastructure for public surveys • Develop image processing engine • Develop survey software system • Ramp-up to VST and VISTA Mission: R&D & operation; science & software; but ...
Community Participation • OPC (approval) • Survey Working Group (design, oversight) • 29 participants (2 committees) • 24 institutes • 7 member states • Visitor Program (operation/development) • 43 participants • 15 institutes • 7 member states Full & broad community involvement in every aspect of the project
EIS Team responsibilities: • Observations (preparation/observing) • Software Development: • Infrastructure (GUIs, database, architecture) • Image processing engine • Scientific algorithms • System integration & tests • Hardware procurement • Preparation, verification & delivery of survey products • WEB development & maintenance • Publications & reports • Recruitment of visitors & administration of intense visitor program • Composition: • 5-6 FTE/year (astronomers & software developers)
Summary of surveys(07/97- ) • 9 surveys in < 6 years (FORS, FLAMES & VIMOS) • 13 strategies • 3 Telescopes (NTT, VLT, 2.2m) • 5 imagers (EMMI, SUSI2, SOFI, ISAAC, WFI) • 22 filters • 240 nights in visitor mode alone done by the team • 73,000 frames of raw data; 37,000 science exposures • WFI 7,000 science; 23,000 total • SOFI 18,200 science; 31,000 total • ISAAC 11,800 science; 21,000 total • 27 public releases (several data products, software, zeropoints) • Observations still ongoing (SOFI 09.04; WFI: 02.05)
Phase-1 (03.97-10.99) • Best-effort • Simple image reduction pipeline using • Available packages (IRAF, Eclipse) • Tools (Drizzle, LDAC, SExtractor) • Wrapper: shell scripts • Limited software development (adaptations, bug-fixing, small-scale new developments) • Help from experts in-house and in the community
Limitations of best-effort approach: • Problems with the data: • Calibration (loss of flux in 1998 release associated to Jitter) • Serious problems with the astrometric calibration of WFI • Rapid increase ( > 6 x) in data volume in 1999 • Reductions mostly manual; no history • Over-reliance on a few people making operation vulnerable & fatigue • Departure of key team members => 6 months interruption in reductions & development • Different environments for optical and infrared • Unsuitable hardware & software
April ‘99 April ‘02 April ‘04 SOFTWARE Phase-2 Phase-1 EIS Data volume: time evolution Project split into 2 phases
Lessons learned • Best-effort approach one-off (not 24 times in 6 years) • unsustainable in the long-term • error-prone, hard to recover • disruptive, leaves no legacy • impedes progress of development (developers become operators) • Need of framework and stable core group to preserve know-how and inherit code • Resource-limited operation requires large degree of automation • Handling large amount of data/information big challenge in survey context (differs from data-in/data-out problem) Requirement: 1) develop new image processing code 2) develop integrated reduction system
EIS data reduction system (06.00-09.04) • Procedures standardized and accessible via GUIs • Access to data/information transparent to user (SE/DAL) • Integrated environment (CVS, ARS, Database, Web) • Common optical/IR image processing engine (90,000 lines of C-code) • System Wrapper (Python > 400,000 lines of code) • XML technology (configuration; logs; Web; database contents) • Self-describing products with quality parameters • Uniqueness, versioning and history of products Medium-size project (by industrial standards) done by non-specialists
Releases • Maximum interval between end of survey and release < 3 years • Products • Night (XMM, DPS, PF) • Stacks • Mosaics • Source catalogs (SExtractor, DAOPHOT) • Catalogs of clusters of galaxies, quasars, low-mass stars • WFI zero-points for 150 nights over 5 years • WFI data covering 29 square degrees • Highlights 2004 • Release of EIS/MVM code • 9 releases in 4 months; 11 releases in 2004 (1 release/month) • Data releases with product logs and READMES • 7000 ISAAC frames; 3000 WFI frames
Raw data Requests: 1367 Products: 84589 Volume: 6.1Tb Survey products Requests: 672 Products: 9292 Volume: 0.93 Tb Software: ~ 62 users Total of last 46 months Requests: 2039 (44/mo) Products: 93851 (2040/mo) Volume: 7 Tb Over project lifetime 27 releases 40 requests/mo Products: > 100,000 12,500 prod/year; 34 prod/day Data Request Statistics
Project Legacy • High-performance, instrument-independent image processing pipeline (tested for all ESO imagers; publicly available) • Integrated, end-to-end data reduction system to monitor & reduce multiple surveys from a single desktop • Survey infra-structure (WG, database, Web interface, release) • Blueprint for a modern data reduction & analysis system • System easily adaptable for different applications
Summary • Over 25 man-years of development • System supports • optical/infrared, single/multi-chip instruments • configurable workflows for un-supervised operations • System consists of several pipelines • Image processing • Photometric calibration • Stack & Mosaics • Catalog (DAOPHOT, SExtractor) • Science applications (plug-ins) • Mature, extensively-tested system before UKIDSS, VST and VISTA commissioning • Work in progress EIS Data Reduction System