Sensor

class wcc_etc.sensor.Sensor(bandpass, pixel_size, read_noise, dark_current, gain, area, temperature=None, qe=1, well_depth=None, bit_depth=None, bias_level=None, meta={})[source]

Bases: _MetaHolder_

A class representing the sensor (detector) properties.

Variables:

bandpass (SpectralElement) – The total throughput (filter + sensor QE + telescope optics).
wavelength (Quantity) – The effective (pivot) wavelength of the bandpass, used to render the PSF.
area (Quantity) – The total area of the sensor.
gain (Quantity) – The sensor gain (e-/ADU).
dark_current (Quantity) – The dark current (e-/s/pix).
read_noise (Quantity) – The read noise (e-/pix).
pixel_size (Quantity) – The pixel size (microns/pix).
bit_depth (int or None) – The ADC bit depth. None if not configured.
bias_level (Quantity) – The additive bias/offset level in ADU.
adc_max (Quantity) – The ADC full-scale clip ceiling in ADU.

classmethod from_name(name)[source]

Create a Sensor instance from a name string ‘kind:band’.

Parameters:: name (str) – Sensor specification, e.g., ‘zwo:r’.
Return type:: Sensor

classmethod from_config(config_or_name)[source]

Create a Sensor instance from a configuration or name.

Parameters:: config_or_name (dict or str) – Configuration dictionary or name string.
Return type:: Sensor

classmethod from_kind_and_band(kind, band)[source]

Load the instance given the detector kind and filter.

Parameters:

kind (str) – Kind of sensor of the WCC: - ‘zwo’ (‘sony’, ‘imx’, ‘imx455’ accepted) - ‘qcmos’
band (str) – Name of the band associated to the sensor (e.g., ‘bb’, ‘u’, ‘r’, ‘z’).

Return type:

Sensor

set_bandpass(bandpass)[source]

Set the sensor bandpass.

Parameters:: bandpass (str or SpectralElement)

get_plate_scale(telescope)[source]

Calculate the plate scale in arcsec/pix.

Parameters:: telescope (Telescope) – The telescope object.
Returns:: The plate scale in arcsec/pix.
Return type:: Quantity

property bandpass: The sensor bandpass (SpectralElement).

property wavelength

The effective (pivot) wavelength of the bandpass.

This is the representative wavelength used to render the monochromatic diffraction PSF. We use the pivot wavelength rather than the peak-transmission wavelength (wpeak): wpeak returns the wavelength of maximum throughput, which for a roughly flat-topped filter is essentially arbitrary within the band and biases the PSF size (the Airy scale is linear in wavelength). The pivot wavelength is the photometrically meaningful effective wavelength of the bandpass and is independent of where the throughput happens to peak.

property area: The sensor area.

property gain: The sensor gain (e-/ct).

property dark_current: The dark current (e-/s/pix).

property read_noise: The read noise (e-/pix).

property pixel_size: The pixel size (um/pix).

property bit_depth: The ADC bit depth (int), or None if not configured.

property bias_level: The additive bias/offset level in ADU (u.ct). Defaults to 0.

property adc_max

2**bit_depth - 1.

Type:: The ADC full-scale (clip ceiling) in ADU (u.ct)