field_from_legacy_photo_calib

lsst.images.fields.field_from_legacy_photo_calib(legacy_photo_calib: LegacyPhotoCalib, bounds: Bounds, instrumental_unit: astropy.units.UnitBase = Unit('electron')) → Field | None

Convert a legacy lsst.afw.image.PhotoCalib into a BaseField object.

Parameters

legacy_photo_calib

Calibration object to convert.

bounds

Bounds of the returned field.

instrumental_unit

The instrumental units the legacy calibration transforms from. These will be used as the denominator of the units of the returned field, with astropy.units.nJy as the numerator.

Returns

BaseField | None

A field that transforms instrumental units to nJy, or None if the given calibration object was an identity mapping for a legacy image that already had nJy pixels.