This note describes raw intensity correction algorithms in the method Detector.calib and their variation on detector type.

LCLS (1) Detector Interface

Detector interface in LCLS (1)

det.calib algorithms

Generic form of this method is

arr = det.calib(evt, cmpars=None, **kwargs)

Regular sequence of applied algorithms

pedestals subtraction from calib/.../pedestals
common mode correction depending on cmpars or calib/.../common_mode or default from PSCalib.CalibParsBase*V1.py
gain correction with gain factors from calib/.../pixel_gain
apply mask depending on **kwargs

regular formula: (common_mode(raw - peds))/gain * mask(**kwargs)

Mask

To construct the mask use **kwargs and algorithms from method mask_v2 from AreaDetector.

TURN OFF common mode correction

For cmpars = None - default constants are used

For regular detectors: cmpars = 0 or cmpars[0] = 0 - OFF

For epix10ka and Jungfrau cmpars[1] = 0 - OFF

Detector dependent algorithms

Spreadsheet below contains comments on detector specific application

Detector type	pedestal subtraction	common mode correction	gain	mask	formula	comments
LCLS (1)
CSPAD	+	default cmpars = (1, 25, 25, 100) cmpars = 0 or cmpars[0] = 0 `- OFF`	*gainmask det.set_gain_mask_factor(gfactor=6.85)	+		gain map extracted from detector configuration data and applied with gfactor gainmask is applied before regular gain factor
CSPAD2x2	+	shape=(185, 388, 2) → common_mode shape=(2, 185, 388) → back to (185, 388, 2) default cmpars = (1,25,25,100)	+	+		shape is converted before common mode correction in order to apply regular CSPAD algorithm then it is converted back to daq shape.
epix100a	+	default cmpars =(4,6,30,30)	+	+
pnCCD	+	default cmpars =(3,350,350,128) or alg #8 (8,5,500)	+	+
Andor3d	+	default cmpars =(2,10,10,cols)	+	+
Princeton	+	default cmpars =(1,50,50,100,1,size,1)	+	+
Camera	+	other Cameras default cmpars = (0,0,0,0), cmpars = 0 or cmpars[0] = 0 `-` `OFF`	+	+
epix10ka	+	`applied for pixels in high gain mode only in combination with mask` `cmpars=None: default (7,2,10,10)` `(*,0,...) - OFF`	pixel_gain constants are used and per event depending on gain range	+	(common_mode(raw - peds)/gain * mask	UtilsEpix10ka.calib_epix10ka_any(det, evt, cmpars=None, **kwa) offsets are already accounted at deployment of pedestals in calib/.../pedestals
Jungfrau	+	applied for pixels in high gain mode only in combination with mask `cmpars=None: default cmpars = (7,1,100,0)` `(*,0,...) - OFF`	pixel_gain and pixel_offset are used and per event depend on gain range	+	(common_mode(raw - peds - offset))/gain * mask	UtilsJungfrau.calib_jungfrau(det, evt, cmpars=(7,3,200,10), **kwa)

LCLS-II Detector Interface

Detector interfase in LCLS-II

Data access code example

    from psana import DataSource
    ds = DataSource(exp=<experiment>,run=<run-number>)
    orun = next(ds.runs())
    det = orun.Detector(<detector-name>)
    for nevt,evt in enumerate(orun.events()):
        print('det.raw.raw(evt).shape  :', det.raw.raw(evt).shape)
        print('det.raw.calib(evt).shape:', det.raw.calib(evt).shape)
        print('det.raw.image(evt).shape:', det.raw.image(evt).shape)

Generic form of this method is

arr = det.raw.calib(evt, **kwa)

Regular formula

common_mode(raw-peds)/gain

Mask

Mask is derived and applied separately as explained in Area detector mask examples or Detector interfase in LCLS-II.

Detector type	pedestal subtraction	common mode correction	gain	mask	formula	comments
LCLS-II
epix10ka	+	cmpars=(7,2,100,10)	+	-		calib_epix10ka_any(det.raw, evt, cmpars=None, **kwa) see UtilsEpix10ka
epix100a	+	cmpars = (7,7,100,10)	+	-		calib_epix100(det.raw, evt, cmpars=None, **kwa) UtilsEpix100
opal	+	-	+	-	(raw-peds)/gain	opal_base
piranha4	+	-	+	-	(raw-peds)/gain	piranha4_base

Method det.calib algorithms

LCLS (1) Detector Interface

det.calib algorithms

Generic form of this method is

Regular sequence of applied algorithms

Mask

TURN OFF common mode correction

Detector dependent algorithms

LCLS-II Detector Interface

Generic form of this method is

Regular formula

Mask

References