Calibrating Photometry

Exporting to AAVSO

Once you have calibrated magnitudes for your target and a check star, you can write a file in the AAVSO Extended File Format that the AAVSO WebObs loader accepts. Stellarphot’s writer produces an ensemble submission (CNAME=ENSEMBLE, CMAG=na) with one target star and one check star, paired observation-by-observation by (date-obs, passband).

The writer expects the passband column to already contain valid AAVSO filter names. If you started from instrumental filter names, use a PassbandMap when constructing PhotometryData and the column will be remapped in place.

Example

from stellarphot.settings import AAVSOSubmissionHeader

header = AAVSOSubmissionHeader(
    type="EXTENDED",
    obscode="ABC",
    software="stellarphot 1.4",
    delim="comma",
    date_format="JD",
)

phot_data.write_aavso_extended(
    "submission.csv",
    header=header,
    target_star_id=1,
    target_name="V0533 Her",
    check_star_id=6,
    check_name="000-BLS-123",
    chart="X12345",
    mag_column="mag_inst_cal",
    mag_error_column="mag_inst_cal_error",
    trans=False,
)

The mag_column and mag_error_column arguments name the calibrated magnitude column and its uncertainty column to read for the target and the check star.

Note

This release supports DATE=JD only. The AAVSO spec also allows HJD and EXCEL dates; using either currently raises NotImplementedError. The writer always emits #OBSTYPE=CCD and MTYPE=STD (consistent with ensemble photometry using standardized magnitudes).