The Advanced Exposure Time Calculator (AETC) is a tool to simulate images of astrophysical objects obtained with any combination of telescope, instrument and given passband using a suitable set of parameters that define the configuration of the equipment used for the observations. The tool provides count rates and its distribution over the focal plane, through the proper definition of the PSF, of virtually any telescope equipped with an imager provided that its configuration is assessed. Moreover a detailed simulation of the observed fields can be simulated including stars, galaxies and more complex objects providing template of the targets.

- Database and Catalogues

    • ASDS - Stellar spectra, in the UV, optical and IR spectral ranges

    • ADPS - Photometric systems

ZBLLAC - A spectroscopic library of BL Lac objects.

This website reports a database of optical spectra of BL Lac objects collected from various literature sources. The targets are listed in an active table yielding this basic information: Name of object with the link to NED, Coordinates (RA, DEC), Redshift or lower limit (when available), and the reference to published papers with the spectra. For each object a figure and an ascii table of the calibrated spectrum are provided. See

- Isocrone

    • Isochrones - Stellar evolutionary tracks, isochrones, and bolometric corrections

    • CMD - Web interface for computing isochrones, luminosity functions, etc

    • PARAM - Web interface for the Bayesian estimation of stellar parameters

  • Simulations of stellar counts in any position of the sky