pyastrobackend package

Submodules

pyastrobackend.ASCOMBackend module

pyastrobackend.AlpacaBackend module

pyastrobackend.BackendConfig module

pyastrobackend.BackendConfig.get_backend(backend_name)

Returns a backend object for the requested backend.

Parameters

backend_name (str) – Name of desired backend.

Raises

Exception – If unavailable backend requested raises exception.

Returns

Backend instance

Return type

Backend object

pyastrobackend.BackendConfig.get_backend_choices()

Returns all valid values for the backend name.

Returns

Names of all possible backends.

Return type

List[str]

pyastrobackend.BackendConfig.get_backend_for_os()

Return the backend matching the current system.

If the environmental variable “PYASTROBACKEND” is defined it will override the default value.

Returns

Name of the default backend for this platform.

Return type

str

pyastrobackend.BaseBackend module

class pyastrobackend.BaseBackend.BaseCamera

Bases: object

Definition of the camera class to be subclassed by actual classes implementing a particular camera driver.

abstract check_exposure()

Check if exposure is complete.

Returns

True if exposure complete.

Return type

bool

abstract check_exposure_success()

Check if exposure was successful - only valid if check_exposure() returns True.

Returns

True if exposure complete.

Return type

bool

abstract connect(name)

Connect to device.

Parameters

name – Name of driver.

Returns

True on success.

Return type

bool

abstract disconnect()

Disconnect from device.

abstract get_binning()

Return pixel binning.

Returns

A tuple containing the X and Y binning.

Return type

(int, int)

abstract get_camera_description()

Get the camera name - result depends on backend in use.

Returns

Description for camera device.

Return type

str

abstract get_camera_gain()

Return gain for camera (not all cameras support).

Returns

Camera gain

Return type

float

abstract get_camera_name()

Get the camera name - result depends on backend in use.

Returns

Name of camera device.

Return type

str

abstract get_cooler_power()

Get cooler power use (percentage of maximum).

Returns

Cooler power level.

Return type

float

abstract get_cooler_state()

Get cooler state.

Returns

True if cooler is on.

Return type

bool

abstract get_current_temperature()

Return current camera temperature.

Returns

Temperature (C)

Return type

float

abstract get_driver_info()

Get information about camera - result depends on backend in use.

Returns

Driver information about camera device.

Return type

str

abstract get_driver_version()

Get version information about camera - result depends on backend in use.

Returns

Driver version information.

Return type

str

abstract get_egain()

Return gain for camera as e- per ADU.

Returns

Camera gain

Return type

float

abstract get_exposure_progress()

Get percentage completion of exposure. Use supports_progress() to test if driver supports this call.

Returns

Percentage completion of exposure.

Return type

int

abstract get_frame()

Return region of interest (ROI) for image capture.

Returns

A tuple containing the upper left (X, Y) for ROI and width/height.

Return type

(int, int, int, int)

abstract get_image_data()

Return image data from last image taken.

Returns

Image data or None if not available.

abstract get_max_binning()

Return maximum pixel binning supported.

Returns

Maximum binning value.

Return type

int

abstract get_pixelsize()

Return pixel size for camera sensor.

Returns

A tuple containing the X and Y pixel sizes.

Return type

(float, float)

abstract get_settings()

Returns most settings for camera as dict. Useful for RPC drivers to reduce round trips.

Following keys (not all will get values on all drivers):

  • binning: (tuple) X, Y binning

  • framesize: (tuple) Width, height of sensor

  • roi: (tuple) Upper left corner and width, height of roi

  • pixelsize: (tuple) X, Y pixel size

  • egain: (float) Gain of camera in e-/ADU

  • camera_gain: (float) Internal gain of camera

  • camera_offset: (float) Internal offset of camera

  • camera_usbbandwidth: (int) Internal USB traffic settings of camera

  • camera_current_temperature: (float) Current temperature of camera

  • camera_target_temperature: (float) Target temperature of camera

  • cooler_state: (bool) Cooler on/off status

  • cooler_power: (float) Power (0-100%) level of cooler

Returns

Dictionary of settings

Return type

dict

abstract get_size()

Return size of sensor in pixels.

Returns

A tuple containing the X and Y pixel sizes.

Return type

(int, int)

abstract get_state()

Get camera state.

Returns

-1

Camera State unknown

0 Camera idle

2 Camera is busy (exposing)

5 Camera error

Rtype int

abstract get_target_temperature()

Return current target camera cooler temperature.

Returns

Target cooler temperature (C)

Return type

float

abstract has_chooser()

Test if a device chooser UI (ie., ASCOM) is available or not.

Returns

True if chooser available, False otherwise.

Return type

bool

abstract is_connected()

Test if a device is connected.

Returns

True if connected, False otherwise.

Return type

bool

abstract save_image_data()

Save image data from last image taken to file. NOTE: Not availale for all backends - check with supports_saveimage().

Parameters

filename – Filename for output file

Ptype str

Returns

Image data or None if not available.

abstract set_binning(binx, biny)

Set pixel binning.

Parameters

  • binx – X binning

  • biny – Y binning

Returns

True on success.

Return type

bool

abstract set_camera_gain(gain)

Set gain for camera (not all cameras support).

Returns

True on success.

Return type

bool

abstract set_cooler_state(onoff)

Set cooler on or off

Parameters

onff – True to turn on camera.

Returns

True on success.

Return type

bool

abstract set_frame(minx, miny, width, height)

Set region of interest (ROI) for image capture.

Parameters

  • minx – Leftmost extent of ROI.

  • miny – Uppermost extent of ROI.

  • width – Width of ROI.

  • height – Height of ROI.

Returns

True on success.

Return type

bool

abstract set_target_temperature(temp_c)

Set target camera cooler temperature.

Parameters

temp_c – Target cooler temperature (C)

Returns

True on success.

Return type

bool

abstract show_chooser(last_choice)

Launch chooser for driver.

Use has_chooser() to test if one is available for a given backend/camera.

Returns

True on success.

Return type

bool

abstract start_exposure(expos)

Start an exposure.

Parameters

expos – Exposure length (seconds)

Ptype float

Returns

True on success.

Return type

bool

abstract stop_exposure()

Stop exposure.

Returns

True on success.

Return type

bool

abstract supports_progress()

Check if exposure progress is supported.

Returns

True if progress info is available.

Return type

bool

abstract supports_saveimage()

Test if drive has ‘saveimage’ method.

Returns

True if available, False otherwise.

Return type

bool

class pyastrobackend.BaseBackend.BaseDeviceBackend

Bases: object

Definition of the backend class to be subclassed by actual classes implementing a particular backend.

A backend represents the communication mechanism for the different device actions to interact with the actual device drivers underneath. For INDI this would be the indi-server. For ASCOM it is a placeholder as there is no actual conduit since all calls are within the process.

abstract connect()

Connect to the backennd.

abstract disconnect()

Disconnect from backend.

abstract isConnected()

Test to see if backend is connected.

Returns

True if connected, False otherwise.

Return type

bool

abstract newCamera()

Create a new BaseCamera reference.

Returns

BaseCamera object.

Return type

BaseCamera

abstract newFilterWheel()

Create a new BaseFilterWheel reference.

Returns

BaseFilterWheel object.

Return type

BaseFilterWheel

abstract newFocuser()

Create a new BaseFocuser reference.

Returns

BaseFocuser object.

Return type

BaseFocuser

abstract newMount()

Create a new BaseMount reference.

Returns

BaseMount object.

Return type

BaseMount

class pyastrobackend.BaseBackend.BaseFilterWheel

Bases: object

abstract connect(name)

Connect to device.

Parameters

name – Name of driver.

Returns

True on success.

Return type

bool

abstract disconnect()

Disconnect from device.

abstract get_names()

Get names of all filter positions.

Returns

List of filter names.

Return type

list

abstract get_num_positions()

Get number of filter positions.

Returns

Number of filter positions

Return type

int

abstract get_position()

Get position of filter wheel. First position is 0!

Returns

Position of filter wheel.

Return type

int

abstract get_position_name()

Get name of filter at current position.

Returns

Name of current filter.

Return type

str

abstract has_chooser()

Test if a device chooser UI (ie., ASCOM) is available or not.

Returns

True if chooser available, False otherwise.

Return type

bool

abstract is_connected()

Test if a device is connected.

Returns

True if connected, False otherwise.

Return type

bool

abstract is_moving()

Check if filter wheel is moving.

Returns

True if filter wheel is moving.

Return type

bool

abstract set_position(abspos)

Set position of filter wheel. First position is 0!

Parameters

abspos – New position of filter wheel.

Returns

True on success.

Return type

int

abstract set_position_name(name)

Set position of filter wheel by filter name..

Parameters

name – Name of new position of filter wheel.

Returns

True on success.

Return type

int

abstract show_chooser(last_choice)

Launch chooser for driver.

Use has_chooser() to test if one is available for a given backend/camera.

Returns

True on success.

Return type

bool

class pyastrobackend.BaseBackend.BaseFocuser

Bases: object

abstract connect(name)

Connect to device.

Parameters

name – Name of driver.

Returns

True on success.

Return type

bool

abstract disconnect()

Disconnect from device.

abstract get_absolute_position()

Get absolute position of focuser.

Returns

Absolute position of focuser.

Return type

int

abstract get_current_temperature()

Get temperature from focuser.

Returns

Temperature (C).

Return type

float

get_max_absolute_position()

Get maximum possible absolute position of focuser.

Returns

Absolute maximum possible position of focuser.

Return type

int

abstract has_chooser()

Test if a device chooser UI (ie., ASCOM) is available or not.

Returns

True if chooser available, False otherwise.

Return type

bool

abstract is_connected()

Test if a device is connected.

Returns

True if connected, False otherwise.

Return type

bool

abstract is_moving()

Check if focuser is moving.

Returns

True if focuser is moving.

Return type

bool

abstract move_absolute_position(abspos)

Move focuser to absolute position.

Parameters

abspos – Target position for focuser.

Returns

True on success.

Return type

bool

abstract show_chooser(last_choice)

Launch chooser for driver.

Use has_chooser() to test if one is available for a given backend/camera.

Returns

True on success.

Return type

bool

abstract stop()

Stop focuser motion..

Returns

True on success.

Return type

bool

class pyastrobackend.BaseBackend.BaseMount

Bases: object

abstract abort_slew()

Abort slew.

Returns

True on success.

Return type

bool

abstract can_park()

Test if a mount can park.

Returns

True if mount can park.

Return type

bool

abstract connect(name)

Connect to device.

Parameters

name – Name of driver.

Returns

True on success.

Return type

bool

abstract disconnect()

Disconnect from device.

abstract get_pier_side()

Returns backend specific pier side information. NOTE: NOT recommended for use as ASCOM and INDI may give different results for different drivers - not tested extensively at all so use with caution.

Returns

‘EAST’, ‘WEST’ or None if unknown.

abstract get_position_altaz()

Get alt/az position of mount.

Returns

Tuple of (alt, az) in degrees.

Return type

(float, float)

abstract get_position_radec()

Get RA/DEC position of mount.

Returns

Tuple of (ra, dec) with ra in decimal hours and dec in degrees.

Return type

(float, float)

abstract get_side_physical()

Get physical side of mount. NOTE: NOT tested extensively with all INDI drivers so it is recommended to test results for ‘normal’ and ‘through the pole’ positions on both side of the pier with a given mount driver!

Returns

‘EAST’, ‘WEST’ or None if unknown.

abstract get_side_pointing()

Get side of meridian where mount is pointing. NOTE may not be same as result from get_side_physical() if counterweights are pointing up, etc! NOTE: NOT tested extensively with all INDI drivers so it is recommended to test results for ‘normal’ and ‘through the pole’ positions on both side of the pier with a given mount driver!

Returns

‘EAST’, ‘WEST’ or None if unknown.

abstract get_tracking()

Get mount tracking state.

Returns

True if tracking.

Return type

bool

abstract has_chooser()

Test if a device chooser UI (ie., ASCOM) is available or not.

Returns

True if chooser available, False otherwise.

Return type

bool

abstract is_connected()

Test if a device is connected.

Returns

True if connected, False otherwise.

Return type

bool

abstract is_parked()

Test if mount is parked.

Returns

True if mount is parked.

Return type

bool

abstract is_slewing()

Test if mount is slewing.

Returns

True if mount is slewing.

Return type

bool

abstract park()

Park mount.

Returns

True on success.

Return type

bool

abstract set_tracking(onoff)

Enable/disable mount tracking.

Parameters

onoff – Flag to turn tracking on/off.

Returns

True on success.

Return type

bool

abstract show_chooser(last_choice)

Launch chooser for driver.

Use has_chooser() to test if one is available for a given backend/camera.

Returns

True on success.

Return type

bool

abstract slew(ra, dec)

Slew mount to RA/DEC position.

Parameters

  • ra – RA in decimal hours.

  • dec – DEC in degrees.

Returns

True on success.

Return type

bool

abstract sync(ra, dec)

Sync mount to RA/DEC position.

Parameters

  • ra – RA in decimal hours.

  • dec – DEC in degrees.

Returns

True on success.

Return type

bool

abstract unpark()

Unark mount.

Returns

True on success.

Return type

bool

pyastrobackend.INDIBackend module

pyastrobackend.RPCBackend module

RPC solution

class pyastrobackend.RPCBackend.DeviceBackend(mainThread=True)

Bases: pyastrobackend.BaseBackend.BaseDeviceBackend

connect()

Connect to the backennd.

disconnect()

Disconnect from backend.

isConnected()

Test to see if backend is connected.

Returns

True if connected, False otherwise.

Return type

bool

name()
newCamera()

Create a new BaseCamera reference.

Returns

BaseCamera object.

Return type

BaseCamera

newFilterWheel()

Create a new BaseFilterWheel reference.

Returns

BaseFilterWheel object.

Return type

BaseFilterWheel

newFocuser()

Create a new BaseFocuser reference.

Returns

BaseFocuser object.

Return type

BaseFocuser

newMount()

Create a new BaseMount reference.

Returns

BaseMount object.

Return type

BaseMount

pyastrobackend.SimpleDeviceInterface module

Module contents