cabaret.Observatory.generate_image

cabaret.Observatory.generate_image#

Observatory.generate_image(ra: float, dec: float, exp_time: float, dateobs: datetime | None = None, light: int = 1, filter_band: Filters | str = Filters.G, airmass: float = 1.5, n_star_limit: int = 2000, rng: Generator = Generator(PCG64) at 0x741C17446880, seed: int | None = None, timeout: float | None = None, sources: Sources | None = None, wcs: WCS | None = None, fwhm_multiplier: float = 5.0, tap_source: GaiaTAPSource | GaiaSQLiteSource | str | None = None, tracking_ra_rate: float | Quantity = 0.0, tracking_dec_rate: float | Quantity = 0.0, n_trail_samples: int = 50, jitter_sigma: float = 0.0, additional_sources: Sources | None = None) → ndarray[source]#

Generate a simulated image of the sky.

Parameters:

  • ra (float) – Right ascension of the center of the image in degrees.

  • dec (float) – Declination of the center of the image in degrees.

  • exp_time (float) – Exposure time in seconds.

  • dateobs (datetime, optional) – Observation date and time in UTC.

  • light (int, optional) – If 1, simulate light exposure; if 0, simulate dark exposure.

  • filter_band (Filters or str, optional) – Photometric filter to use for the simulation (default: Filters.G).

  • airmass (float, optional) – Airmass value for the observation (default: 1.5).

  • n_star_limit (int, optional) – Maximum number of stars to include in the image.

  • rng (numpy.random.Generator, optional) – Random number generator.

  • seed (int, optional) – Random number generator seed.

  • timeout (float, optional) – The maximum time to wait for the Gaia query to complete, in seconds. If None, there is no timeout. By default, it is set to None.

  • sources (Sources, optional) – A collection of sources with their sky coordinates and fluxes. If provided, these sources will be used instead of querying Gaia.

  • wcs (WCS or None, optional) – World Coordinate System information for the image.

  • fwhm_multiplier (float, optional) – Multiplier to determine the rendering radius around each star (default: 5.0).

  • tracking_ra_rate (float, u.Quantity, optional) – Telescope tracking rate offset in right ascension, in angular sky coordinate units per second as expected by generate_image. Non-zero values simulate RA drift/trailing during the exposure.

  • tracking_dec_rate (float, u.Quantity, optional) – Telescope tracking rate offset in declination, in angular sky coordinate units per second as expected by generate_image. Non-zero values simulate Dec drift/trailing during the exposure.

  • n_trail_samples (int, optional) – Number of samples used to integrate source motion across the exposure when simulating star trails. Larger values give smoother trails at higher computational cost.

  • jitter_sigma (float, optional) – 1-sigma guiding jitter in arcsec applied per trail sample (default: 0). Larger values produce broader motion blur from random tracking variations.

  • additional_sources (Sources, optional) – Additional Sources to render in every image on top of the base source set. When supplied, they are appended to the sources obtained from Gaia, or to the explicitly provided sources collection; they do not replace those base sources.