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Focus Class

azcam.tools.focus.Focus

Bases: Tools

Class for focusing a camera.

Either the telescope or instrument may be moved for focus adjustment. The focus sequence performed is:

  • integrate
  • move focus
  • shift detector (2x last time)
  • (repeat above steps)
  • readout
  • return to starting focus position
  • save image

__init__(tool_id='focus', description=None)

Create focus tool.

_get_focus()

Get focus using default focus_id.

_set_focus(focus_value)

Set focus using default focus_id and focus_type

abort()

Abort focus exposure.

initialize()

Initialize focus routine.

run(exposure_time=1.0, number_exposures=7, focus_step=30, detector_shift=10)

Execute the focus sequence. If focus.set_pars() was previously called then those values are used and input here is ignored. Args: number_exposures: Number of exposures in focus sequence. focus_step: Number of focus steps between each exposure in a frame. detector_shift: Number of rows to shift detector for each focus step. exposuretime: Exposure time in seconds.

save_keywords()

Save focus related keywords for image header.

set_pars(exposure_time, number_exposures=7, focus_step=30, detector_shift=10)

Set focus related parameters. Args: number_exposures: Number of exposures in focus sequence. focus_step: Number of focus steps between each exposure in a frame. detector_shift: Number of rows to shift detector for each focus step. exposuretime: Exposure time i seconds.

Focus Parameters

Parameters may be changed from the command line as: focus.number_exposures=7 or focus.set_pars(1.0, 5, 25, 15).

focus.number_exposures = 7
Number of exposures in focus sequence
focus.focus_step = 30
Number of focus steps between each exposure in a frame
focus.detector_shift = 10
Number of rows to shift detector for each focus step
focus.focus_position
Current focus position
focus.exposure_time = 1.0
Exposure time (seconds)
focus.focus_component = "instrument"
Focus component for motion - "instrument" or "telescope"
focus.focus_type = "absolute"
Focus type, "absolute" or "step"
focus.set_pars_called = 1
Flag to not prompt for focus position
focus.move_delay = 3
Delay in seconds between focus moves