gabriel-p/phot_bh73

DEPRECATED

Scripts

als_compare

Compares the magnitudes of two als files.

apass_compare

Reads a given photometry file (.als, .mag, .obs, .dat) and compares it with the photometry obtained from APASS. Creates the apass_compare.png image.

daom_obs_prep

Checks the star density in each .mag file output by DAOMASTER, and generates the daom.obs file by adding the airmass columns to the daom.raw file selected. Creates the daomaster_wt_X.png images.

final_phot

Takes the daom.obs and fit_coeffs.dat files and generates the calibrated photometry using the values obtained with Python. It creates the BH73_phot.dat final photometry and the final_phot.png image.

phot_compare

Compares the final photometry obtained with IRAF using the invertfit task, with the Python photometry generated by the above script. It creates the phot_compare.png file.

psf_compare

Compares the (aperture corrected) magnitudes in a als file (IRAF) with the magnitudes obtained with the Python scripts.

Photometry steps

1. The standard transformation coefficients were obtained using the Python scripts: fitstats, align_crop, id_standards, aperphot_standards, fit_standard. I also used the usual IRAF tasks in the folder 1_TRANSF_COEFFS. Both methods seem to match pretty well (see description of final_phot.py script) The aperture used was 15 px and the extinction coefficients were obtained with the auxiliary ext_coeff script: U .442, B .232, V .136, I .048
2. The PSF photometry was performed with IRAF, through the psfphot.cl task. Files are stored in the 2_PSF folder. The output als.1 files (corrected by aperture with the previous task) were transformed to the required DAOMASTER format (.txt) with the IRAF task txdump.
3. These files were processed with daomaster_auto using a match radius from 30 px to 2 px, and a transformation of degree 4 (with only 2 degrees the I filters could not be matched) The required initial x,y translations are stored in the list (and daom.mch) file. The final output file by DAOMASTER is daom.raw, which is converted to daom.obs (we use daom_4.raw) by adding the airmasses of the longest exposure as columns (in the same order as the photometric columns: V, B, U, I) All files are stored in the folder 3_DAOM. The match.py script is unable to produce a correct match. There's something probably wrong with the linear equations solution.
4. Finally, the magnitudes are transformed into the standard system using the coefficients obtained in 1. (stored in fit_coeffs.dat) with the final_phot.py script. I also used the invertfit task, and the results are stored in the 4_INVERTFIT folder.