autolens.SimulatorImaging#

class SimulatorImaging[source]#

Bases: SimulatorImaging

A class representing a Imaging observation, using the shape of the image, the pixel scale, psf, exposure time, etc.

Parameters

  • psf (Kernel2D) – An arrays describing the PSF kernel of the image.

  • exposure_time (float) – The exposure time of the simulated imaging.

  • background_sky_level (float) – The level of the background sky of the simulated imaging.

  • normalize_psf (bool) – If True, the PSF kernel is normalized so all values sum to 1.0.

  • read_noise (Optional[float]) – The level of read-noise added to the simulated imaging by drawing from a Gaussian distribution with sigma equal to the value read_noise.

  • add_poisson_noise (bool) – Whether Poisson noise corresponding to photon count statistics on the imaging observation is added.

  • noise_if_add_noise_false (float) – If noise is not added to the simulated dataset a noise_map must still be returned. This value gives the value of noise assigned to every pixel in the noise-map.

  • noise_seed (int) – The random seed used to add random noise, where -1 corresponds to a random seed every run.

Methods

via_deflections_and_galaxies_from

via_galaxies_from

Simulate imaging data for this data, as follows:

via_image_from

Returns a realistic simulated image by applying effects to a plain simulated image.

via_tracer_from

Returns a realistic simulated image by applying effects to a plain simulated image.
via_tracer_from(tracer, grid)[source]#

Returns a realistic simulated image by applying effects to a plain simulated image.

Parameters

  • name –

  • image – The image before simulating (e.g. the lens and source galaxies before optics blurring and Imaging read-out).

  • pixel_scales – The scale of each pixel in arc seconds

  • exposure_time_map – An arrays representing the effective exposure time of each pixel.

  • psf (PSF) – An arrays describing the PSF the simulated image is blurred with.

  • background_sky_map – The value of background sky in every image pixel (electrons per second).

  • add_poisson_noise (Bool) – If True poisson noise_maps is simulated and added to the image, based on the total counts in each image pixel

  • noise_seed (int) – A seed for random noise_maps generation

via_galaxies_from(galaxies, grid)[source]#

Simulate imaging data for this data, as follows:

  1. Setup the image-plane grid of the Imaging arrays, which defines the coordinates used for the ray-tracing.

  2. Use this grid and the lens and source galaxies to setup a tracer, which generates the image of the simulated imaging data.

  3. Simulate the imaging data, using a special image which ensures edge-effects don’t degrade simulator of the telescope optics (e.g. the PSF convolution).

  4. Plot the image using Matplotlib, if the plot_imaging bool is True.

  5. Output the dataset to .fits format if a dataset_path and data_name are specified. Otherwise, return the simulated imaging data instance.