gemini_instruments.f2 package

class gemini_instruments.f2.AstroDataF2(nddata=None, tables=None, phu=None, indices=None)[source]

Bases: gemini_instruments.gemini.adclass.AstroDataGemini

array_section(pretty=False)[source]

Returns the rectangular section that includes the pixels that would be exposed to light. If pretty is False, a tuple of 0-based coordinates is returned with format (x1, x2, y1, y2). If pretty is True, a keyword value is returned without parsing as a string. In this format, the coordinates are generally 1-based.

One tuple or string is return per extension/array, in a list. If the method is called on a single slice, the section is returned as a tuple or a string.

Parameters

pretty (bool) – If True, return the formatted string found in the header.

Returns

  • tuple of integers or list of tuples – Location of the pixels exposed to light using Python slice values.

  • string or list of strings – Location of the pixels exposed to light using an IRAF section format (1-based).

central_wavelength(asMicrometers=False, asNanometers=False, asAngstroms=False)[source]

Returns the central wavelength in meters or the specified units

Parameters
  • asMicrometers (bool) – If True, return the wavelength in microns

  • asNanometers (bool) – If True, return the wavelength in nanometers

  • asAngstroms (bool) – If True, return the wavelength in Angstroms

Returns

The central wavelength setting

Return type

float

data_section(pretty=False)[source]

Returns the rectangular section that includes the pixels that would be exposed to light. If pretty is False, a tuple of 0-based coordinates is returned with format (x1, x2, y1, y2). If pretty is True, a keyword value is returned without parsing as a string. In this format, the coordinates are generally 1-based.

One tuple or string is return per extension/array, in a list. If the method is called on a single slice, the section is returned as a tuple or a string.

Parameters

pretty (bool) – If True, return the formatted string found in the header.

Returns

  • tuple of integers or list of tuples – Location of the pixels exposed to light using Python slice values.

  • string or list of strings – Location of the pixels exposed to light using an IRAF section format (1-based).

detector_section(pretty=False)[source]

Returns the section covered by the detector relative to the whole mosaic of detectors. If pretty is False, a tuple of 0-based coordinates is returned with format (x1, x2, y1, y2). If pretty is True, a keyword value is returned without parsing as a string. In this format, the coordinates are generally 1-based.

One tuple or string is return per extension/array, in a list. If the method is called on a single slice, the section is returned as a tuple or a string.

Parameters

pretty (bool) – If True, return the formatted string found in the header.

Returns

  • tuple of integers or list of tuples – Position of the detector using Python slice values.

  • string or list of strings – Position of the detector using an IRAF section format (1-based).

detector_x_offset()[source]

Returns the offset from the reference position in pixels along the positive x-direction of the detector

Returns

The offset in pixels

Return type

float

detector_y_offset()[source]

Returns the offset from the reference position in pixels along the positive y-direction of the detector

Returns

The offset in pixels

Return type

float

dispersion(asMicrometers=False, asNanometers=False, asAngstroms=False)[source]

Returns the dispersion in meters per pixel as a list (one value per extension) or a float if used on a single-extension slice. It is possible to control the units of wavelength using the input arguments.

Parameters
  • asMicrometers (bool) – If True, return the wavelength in microns

  • asNanometers (bool) – If True, return the wavelength in nanometers

  • asAngstroms (bool) – If True, return the wavelength in Angstroms

Returns

The dispersion(s)

Return type

list/float

dispersion_axis()[source]

Returns the axis along which the light is dispersed.

Returns

Dispersion axis.

Return type

(list of) int (2)

filter_name(stripID=False, pretty=False)[source]

Returns the name of the filter(s) used. The component ID can be removed with either ‘stripID’ or ‘pretty’. If a combination of filters is used, the filter names will be join into a unique string with ‘&’ as separator. If ‘pretty’ is True, filter positions such as ‘Open’, ‘Dark’, ‘blank’, and others are removed leaving only the relevant filters in the string.

Parameters
  • stripID (bool) – If True, removes the component ID and returns only the name of the filter.

  • pretty (bool) – Parses the combination of filters to return a single string value wi the “effective” filter.

Returns

The name of the filter combination with or without the component ID.

Return type

str

gain()[source]

Returns the gain used for the observation. This is read from a lookup table using the read_mode and the well_depth.

Returns

Gain used for the observation

Return type

float

group_id()[source]

Returns a string representing a group of data that are compatible with each other. This is used when stacking, for example. Each instrument and mode of observation will have its own rules. F2’s is quite a mouthful.

Returns

A group ID for compatible data.

Return type

str

nominal_photometric_zeropoint()[source]

Returns the nominal zeropoints (i.e., the magnitude corresponding to a pixel value of 1) for the extensions in an AD object.

Returns

zeropoint values, one per SCI extension

Return type

list/float

non_linear_level()[source]

Returns the level at which the data become non-linear, in ADU.

Returns

Value at which the data become non-linear

Return type

list/int

nonlinearity_coeffs()[source]
observation_type()[source]

Returns the observation type (OBJECT, DARK, BIAS, etc.)

Returns

Observation type

Return type

str

pixel_scale()[source]

Returns the image scale in arcseconds per pixel

Returns

pixel scale

Return type

float

read_mode()[source]

Returns the read mode (i.e., the number of non-destructive read pairs)

Returns

readout mode

Return type

str

read_noise()[source]

Returns the read noise in electrons.

Returns

read noise

Return type

float

saturation_level()[source]

Returns the saturation level (in ADU)

Returns

saturation level

Return type

int/float

telescope_x_offset()[source]

Returns the x offset from origin of this image

Returns

x offset

Return type

float

telescope_y_offset()[source]

Returns the y offset from origin of this image

Returns

y offset

Return type

float

Submodules

gemini_instruments.f2.adclass module

class gemini_instruments.f2.adclass.AstroDataF2(nddata=None, tables=None, phu=None, indices=None)[source]

Bases: gemini_instruments.gemini.adclass.AstroDataGemini

array_section(pretty=False)[source]

Returns the rectangular section that includes the pixels that would be exposed to light. If pretty is False, a tuple of 0-based coordinates is returned with format (x1, x2, y1, y2). If pretty is True, a keyword value is returned without parsing as a string. In this format, the coordinates are generally 1-based.

One tuple or string is return per extension/array, in a list. If the method is called on a single slice, the section is returned as a tuple or a string.

Parameters

pretty (bool) – If True, return the formatted string found in the header.

Returns

  • tuple of integers or list of tuples – Location of the pixels exposed to light using Python slice values.

  • string or list of strings – Location of the pixels exposed to light using an IRAF section format (1-based).

central_wavelength(asMicrometers=False, asNanometers=False, asAngstroms=False)[source]

Returns the central wavelength in meters or the specified units

Parameters
  • asMicrometers (bool) – If True, return the wavelength in microns

  • asNanometers (bool) – If True, return the wavelength in nanometers

  • asAngstroms (bool) – If True, return the wavelength in Angstroms

Returns

The central wavelength setting

Return type

float

data_section(pretty=False)[source]

Returns the rectangular section that includes the pixels that would be exposed to light. If pretty is False, a tuple of 0-based coordinates is returned with format (x1, x2, y1, y2). If pretty is True, a keyword value is returned without parsing as a string. In this format, the coordinates are generally 1-based.

One tuple or string is return per extension/array, in a list. If the method is called on a single slice, the section is returned as a tuple or a string.

Parameters

pretty (bool) – If True, return the formatted string found in the header.

Returns

  • tuple of integers or list of tuples – Location of the pixels exposed to light using Python slice values.

  • string or list of strings – Location of the pixels exposed to light using an IRAF section format (1-based).

detector_section(pretty=False)[source]

Returns the section covered by the detector relative to the whole mosaic of detectors. If pretty is False, a tuple of 0-based coordinates is returned with format (x1, x2, y1, y2). If pretty is True, a keyword value is returned without parsing as a string. In this format, the coordinates are generally 1-based.

One tuple or string is return per extension/array, in a list. If the method is called on a single slice, the section is returned as a tuple or a string.

Parameters

pretty (bool) – If True, return the formatted string found in the header.

Returns

  • tuple of integers or list of tuples – Position of the detector using Python slice values.

  • string or list of strings – Position of the detector using an IRAF section format (1-based).

detector_x_offset()[source]

Returns the offset from the reference position in pixels along the positive x-direction of the detector

Returns

The offset in pixels

Return type

float

detector_y_offset()[source]

Returns the offset from the reference position in pixels along the positive y-direction of the detector

Returns

The offset in pixels

Return type

float

dispersion(asMicrometers=False, asNanometers=False, asAngstroms=False)[source]

Returns the dispersion in meters per pixel as a list (one value per extension) or a float if used on a single-extension slice. It is possible to control the units of wavelength using the input arguments.

Parameters
  • asMicrometers (bool) – If True, return the wavelength in microns

  • asNanometers (bool) – If True, return the wavelength in nanometers

  • asAngstroms (bool) – If True, return the wavelength in Angstroms

Returns

The dispersion(s)

Return type

list/float

dispersion_axis()[source]

Returns the axis along which the light is dispersed.

Returns

Dispersion axis.

Return type

(list of) int (2)

filter_name(stripID=False, pretty=False)[source]

Returns the name of the filter(s) used. The component ID can be removed with either ‘stripID’ or ‘pretty’. If a combination of filters is used, the filter names will be join into a unique string with ‘&’ as separator. If ‘pretty’ is True, filter positions such as ‘Open’, ‘Dark’, ‘blank’, and others are removed leaving only the relevant filters in the string.

Parameters
  • stripID (bool) – If True, removes the component ID and returns only the name of the filter.

  • pretty (bool) – Parses the combination of filters to return a single string value wi the “effective” filter.

Returns

The name of the filter combination with or without the component ID.

Return type

str

gain()[source]

Returns the gain used for the observation. This is read from a lookup table using the read_mode and the well_depth.

Returns

Gain used for the observation

Return type

float

group_id()[source]

Returns a string representing a group of data that are compatible with each other. This is used when stacking, for example. Each instrument and mode of observation will have its own rules. F2’s is quite a mouthful.

Returns

A group ID for compatible data.

Return type

str

nominal_photometric_zeropoint()[source]

Returns the nominal zeropoints (i.e., the magnitude corresponding to a pixel value of 1) for the extensions in an AD object.

Returns

zeropoint values, one per SCI extension

Return type

list/float

non_linear_level()[source]

Returns the level at which the data become non-linear, in ADU.

Returns

Value at which the data become non-linear

Return type

list/int

nonlinearity_coeffs()[source]
observation_type()[source]

Returns the observation type (OBJECT, DARK, BIAS, etc.)

Returns

Observation type

Return type

str

pixel_scale()[source]

Returns the image scale in arcseconds per pixel

Returns

pixel scale

Return type

float

read_mode()[source]

Returns the read mode (i.e., the number of non-destructive read pairs)

Returns

readout mode

Return type

str

read_noise()[source]

Returns the read noise in electrons.

Returns

read noise

Return type

float

saturation_level()[source]

Returns the saturation level (in ADU)

Returns

saturation level

Return type

int/float

telescope_x_offset()[source]

Returns the x offset from origin of this image

Returns

x offset

Return type

float

telescope_y_offset()[source]

Returns the y offset from origin of this image

Returns

y offset

Return type

float

gemini_instruments.f2.lookup module

class gemini_instruments.f2.lookup.ArrayProperties(readnoise, gain, welldepth, linlimit, nonlinlimit, coeffs)

Bases: tuple

property coeffs

Alias for field number 5

property gain

Alias for field number 1

property linlimit

Alias for field number 3

property nonlinlimit

Alias for field number 4

property readnoise

Alias for field number 0

property welldepth

Alias for field number 2