Adjustments for pyscope on real hardware

[pgriffin17]

Solves #125 by implementing a working exposure time logging property in the ascom_camera.py script in my exptime branch and updating the observatory class to use this, which results in the last user-input exposure time being logged to the FITS header if the ASCOM LastExposureDuration function is not implemented in the ASCOM driver.

This builds off of #124 .

[pgriffin17]

Current changelog

• Adds new ASCOM camera properties of _last_exposure_duration and _last_exposure_time

  • These hold temporary exposure duration and image start time values in the case that the camera does not support actual readout of these parameters (as is the case for ZWO ASI290MM Mini).

• Adds LastInputExposureDuration property to ASCOM camera driver

  • This exposes _last_exposure_duration as set by the user.

• Currently the Observatory class has checks on which value to place for EXPTIME and EXPOSURE (this should probably be moved to the ASCOM Camera driver

  • Also adds CAMTIME to FITS header, which is True if the EXPTIME/EXPOSURE is set from the camera's own time or if it is using the user's input time.

• Changes _last_exposure_start_time in maxim driver to use dt.utcnow() instead of time.time().

[pgriffin17]

I've now added a function to ASCOM Camera that will set the image data type appropriately depending on the camera settings. Documentation is shown below:

[pgriffin17]

Fixes #125, #128, and allows pyscope to function on real minimal hardware setups.

• Tested on Losmandy Gemini (1) G11 German Equatorial mount along with ZWO ASI290MM Mini camera.

ASCOM Cameras now have their image arrays transposed by default to match their standard orientation, as well as having their data type set to 16 bit by default, or based off of their MaxADU (as in the documentation or in the screenshot above). This keeps the Observatory class the same as far as the ImageArray property is concerned.

Changelog:

ASCOM Camera related features

• Adds new ASCOM camera properties of _last_exposure_duration and _last_exposure_time
  • These hold temporary exposure duration and image start time values in the case that the camera does not support actual readout of these parameters (as is the case for ZWO ASI290MM Mini).
• Adds LastInputExposureDuration property to ASCOM camera driver
  • This exposes _last_exposure_duration as set by the user.
• Adds new ASCOM camera properties of _image_data_type, and _DoTranspose
  • These store the optimal data type for the images (as set by SetImageDataType()) and whether the ImageArray should be transposed.
• Currently the Observatory class has checks on which value to place for EXPTIME and EXPOSURE (this should probably be moved to the ASCOM Camera driver)
  • Also adds CAMTIME to FITS header, which is True if the EXPTIME/EXPOSURE is set from the camera's own time or if it is using the user's input time.

Observatory class optimizations

• The Observatory class previously had several calls to self.camera.ImageArray within the save_last_image() function. These have now been reduced to one call that is stored in a variable and referenced several times.

Camera driver optimizations

• Changes _last_exposure_start_time in maxim driver and ASCOM camera driver to use dt.utcnow() instead of time.time().

Get Real Hardware Working by changing _read_out_kwargs

• To get real hardware working, adjusted location setting lines to ensure that devices are connected before setting mount parameters
• Also cleared up some Cover Calibrator if statements
• Part of the rotator section caused errors, so added a check to ensure the rotator driver was assigned before checking some kwargs.

Next up is to move EXPTIME/EXPOSURE checks (on using the camera's own exposure time, if it exists, or the user input exposure time) from the Observatory class to the ASCOM Camera driver.

[pgriffin17]

Now I have moved EXPTIME/EXPOSURE checks (on using the camera's own exposure time, if it exists, or the user input exposure time) from the Observatory class to the ASCOM Camera driver.

[pgriffin17]

This pull request:

closes #125
closes #128

[pgriffin17]

Updated to use astropy.Time.now() instead of datetime