preproc.py

Collection of pre-processing functions for general use.

Functions

• choose_calib - calibration images visualization and selection.
• choose_science - display science images for verification by user.
• mkmaster - make master calibration frames (bias, dark, flat).

##choose_calib <> choose_calib(instrument, ftype, [workdir='./', cams=[0,1,2,3], auto=False, reject_sat=True, amin=0.2, amax=0.8, save_select=True, figsize=(8,5), noplot=False])

Either auto-select or display calibration images for user verification.

####Params

• instrument {str}: Instrument name defined in specific_instruments.py (e.g. ratir)
• ftype {str}: Type of calibration frames (e.g. bias, dark, flat).
• workdir {str, optional}: Location of calibration frames (current directory if unspecified), followed by a slash.
• cams {list of str, optional}: Camera numbers, default is all. (e.g. [0,1,2,3])
• auto {bool, optional}: Automated frame selection. If bias, will select all, if flat will select non-saturated frames with sufficient counts.
• reject_sat {bool, optional}: Reject frames with saturated pixels.
• amin {float, optional}: Minimum fraction of saturation value for median (automated).
• amax {float, optional}: Maximum fraction of saturation value for median (automated).
• save_select {bool, optional}: Save dictionary of selected frames to python pickle file.
• figsize {tuple of int}: Dimensions of figure used to display frames for selection.
• noplot {bool, optional}: Don't display calibration frames.

####Example

dict = choose_calib( instrument='ratir', 
                     ftype='bias',
                     workdir='./fits/bias/',
                     cams =[0,1,2,3] )

Note: Call mkmaster using resulting dictionary, or path to pickle file (if save_select=True).

##choose_science <> choose_science(instrument, [workdir='./', targetdir='./', cams=[0,1,2,3], auto=False, save_select=True, figsize=(10,10), calibrate=False, noplot=False])

Display science images for verification by user.

####Params

• instrument {str}: Instrument name defined in specific_instruments.py (e.g. ratir)
• workdir {str, optional}: Location of all science frames (current directory if unspecified), followed by a slash.
• targetdir {str, optional}: Location of selected science frames (current directory if unspecified), followed by a slash.
• cams {list of str, optional}: Camera numbers, default is all. (e.g. [0,1,2,3])
• auto {str, optional}: Select all science frames.
• save_select {bool, optional}: Save dictionary of selected frames to python pickle file.
• figsize {tuple of int}: Dimensions of figure used to display frames for selection.
• calibrate {bool, optional}: Subtract master bias, master dark to science frames, and divide by master flat before displaying.
• noplot {bool, optional}: Don't display science frames.

####Example

dict = choose_science( instrument='ratir', 
                       workdir='./fits/science',
                       targetdir='./fits/science/selected', 
                       cams=[0,1,2,3], 
                       calibrate=True )

##mkmaster <> mkmaster(instrument, fn_dict, mtype, [fmin=5])

Make master calibration frames (bias, dark, flat). Currently no outlier rejection other than median combine.

####Params

• instrument {str}: Instrument name defined in specific_instruments.py (e.g. ratir)
• fn_dict {dict or str}: Dictionary output by choose_calib containing organized FITS file names. Can also provide filename of pickled dictionary.
• mtype {str}: Type of master frame. Should be either bias, dark or flat.
• fmin {str, optional}: Minimum number of files needed to make a master frame.

####Example

mkmaster( instrument='ratir', 
          fn_dict='./output_from_choose_calib'
          mtype='bias' )