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The Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) is a high impact scientific program which will see its final official release open to the world in 2012. That release will seal the legacy aspect of the survey which has already produced a large collection of scientific articles with topics ranging from cosmology to the Solar system. The survey core science was focused on dark energy and dark matter: the full realization of the scientific potential of the data set gathered between 2003 and 2009 with the MegaCam wide-field imager mounted at the CFHT prime focus is almost complete with the Supernovae Legacy Survey (SNLS) team preparing its third and last release (SNLS5), and the CFHTLenS team planning the release based around the cosmic shear survey later this year. While the data processing center TERAPIX offered to the CFHTLS scientific community regular releases over the course of the survey in its data acquisition phase (T0001-T0006), the final release took three years to refine in order to produce a pristine data collection photometrically calibrated at better than the percent both internally and externally over the total survey surface of 155 square degrees in all five photometric bands (u*, g', r', i', z'). This final release, called T0007, benefits from the various advances in photometric calibration MegaCam has benefited through the joint effort between SNLS and CFHT to calibrate MegaCam at levels unexplored for an optical wide-field imager. T0007 stacks and catalogs produced by TERAPIX will be made available to the world at CADC while the CDS will offer a full integration of the release in its VO tools from VizieR to Aladin. The photometric redshifts have been produced to be released in phase with the survey. This proceeding is a general introduction to the survey and aims at presenting its final release in broad terms., Observatory Operations: Strategies, Processes, and Systems IV, July 4-6, 2012, Amsterdam, Netherlands, Series: Proceedings of SPIE

Interoperability in Virtual Observatories is based on standards for interchange formats, and protocols. Using real science cases, we present example VO tools based on the AVO prototypes and the CDS services, which implement the new and emerging VO standards. We discuss how these standards, such as VOTable, UCDs and data models enable interoperability between software components, and provide efficient and flexible means for data access. We show how UCDs are used in catalogue filtering and selection of relevant columns. We also demonstrate a simple yet powerful method for accessing data from image archives, customized data sets and local data within a single environment.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Building an automated classifier for high-energy sources provides an opportunity to prototype approaches to building the Virtual Observatory with a substantial immediate scientific return. The ClassX collaboration is combining existing data resources with trainable classifiers to build a tool that classifies lists of objects presented to it. In our first year the collaboration has concentrated on developing pipeline software that finds and combines information of interest and in exploring the issues that will be needed for successful classification. ClassX must deal with many key VO issues: automating access to remote data resources, combining heterogeneous data and dealing with large data volumes. While the VO must attempt to deal with these problems in a generic way, the clear science goals of ClassX allow us to act as a pathfinder exploring particular approaches to addressing these issues.

The Centre de Donnees astronomiques de Strasbourg (CDS) develops a set of value-added services, widely used for information retrieval, observation preparation, data interpretation, etc. SIMBAD, VizieR, Aladin and the 'Dictionary of Nomenclature' integrate heterogeneous selected information from observatory archives, sky surveys and publications. Each service organizes information in a different way (astronomical objects, tables, images with overlays), and the CDS hub allows versatile information retrieval, e.g. looking for known information in a given region of the sky, including observations from ground- and space-based instruments, or searching by criteria in large data sets. Links among the CDS services, and with other reference on-line information systems, such as observatory and survey archives or publications, permit comprehensive searches in a wide variety of resources. Shared exchange standards and generic tools such as the GLU are essential for the building of links. XML is a key tool for further information integration, and Aladin is a precursor of an integration tool, relying on FITS and XML. New functionalities will be developed at CDS in the context of the Virtual Observatory, e.g. for data mining and management of very large catalogues.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.