Instrument (instrument)


The ctapipe.instrument module contains classes and methods for describing the instrumental layout and configuration.

This module is under heavy restructuring and should not be considered ready for general use, except for the CameraGeometry object, which provides pixel positions, etc.

Hierarchy of InstrumentDescription Classes

  • SubarrayDescription (describes full subarray)

    • TelescopeDescription (describes a single telescope)

      • OpticsDescription (describes the optical support structure and mirror)

      • CameraDescription (describes the camera)

        • CameraGeometry (describes the geometrical aspects of the camera, e.g. only that which is needed by reconstruction methods)

        • CameraReadout (describes the aspects related to the waveform readout e.g. sampling rate and reference pulse shape.geometrical aspects of the camera, e.g.

        • [to come: classes to hold more detailed hardware-level info about a camera]

Other Instrumental Data

Atmosphere Profiles

With the instrument module you can also load standard atmosphere profiles, which are read from tables located in ctapipe_resources by default

The function get_atmosphere_profile_functions() returns two interpolation functions that convert between height and atmosphere thickness.


ctapipe.instrument Package



Gives atmospheric profile as a continuous function thickness( altitude), and it’s inverse altitude(thickness) in m and g/cm^2 respectively.

guess_telescope(n_pixels, focal_length)

From n_pixels of the camera and the focal_length, guess which telescope we are dealing with.


CameraDescription(camera_name, geometry, readout)

Describes a Cherenkov camera and its associated CameraGeometry and CameraReadout

CameraGeometry(camera_name, pix_id, pix_x, …)

CameraGeometry is a class that stores information about a Cherenkov Camera that us useful for imaging algorithms and displays.

CameraReadout(camera_name, sampling_rate, …)

TelescopeDescription(name, tel_type, optics, …)

Describes a Cherenkov Telescope and its associated OpticsDescription and CameraDescription

OpticsDescription(name, num_mirrors, …[, …])

Describes the optics of a Cherenkov Telescope mirror

SubarrayDescription(name[, tel_positions, …])

Collects the TelescopeDescription of all telescopes along with their positions on the ground.


Supported Pixel Shapes Enum