Vis Master Flat Frame Product

Metadata

Data product name	DpdVisMasterFlatFrame
Data product custodian	VIS
Name of the Schema file	euc-vis-MasterFlatFrame.xsd
Processing Element(s) creating/using the data product	Final data product of the Master Flat (PRNU) Calibration pipeline. Used by the PRNU Correction task in several pipelines: (ProcessField, LargeFlat, BrighterFatter).
Processing function using the data product	VIS

Proposed for inclusion in EAS/SAS

Yes

Data product elements

Header	object of type sys:genericHeader
Data	object of type vis:visMasterFlatFrame
QualityFlags	object of type dqc:sqfPlaceHolder
Parameters	object of type ppr:genericKeyValueParameters

Detailed description of the data product

The Master Flat Calibration Pipeline result is created from a series of flat-field calibration exposures. It contains a Master PRNU image which describes the Pixel Response Non-Uniformity (PRNU) of each pixel in each VIS quadrant. This image is a MEF FITS containing 144 extension. Each quadrant is identified by the keyword EXTNAME. The units of this product is ADU

PRNU is calibrated using a set of PRNU exposures, illuminated by an LED in the Calibration Unit (CU) which sits in front of the VIS focal plane. The master flat is produced using a combinaison of the 4 LED of the CU.

Name of file:

EUC_VIS_MSR-FLA-[LED]-[Fluence]__[YYYYMMDDThhmmss.s]Z.fits

where the date is the production date.

The product contains a Flagmap FITS file, in the format of VIS quadrant. The Master PRNU will set the bits for flagging hot and cold pixels. The Flagmap data format is defined in the data model here and is described in Vis Flag Map Product.

The product contains an LED Profile FITS file which quantifies the illumination of the quadrant by the calibration unit (CU) LED.

Detailed Algorithm information can be viewed in tech note: https://euclid.roe.ac.uk/dmsf/files/16476/view

Description of the effect

Each pixel in a CCD has slightly different levels of response to light, due to manufacturing irregularities. The PRNU of a pixel is defined here as the level of responsiveness relative to its near-by neighbours, where the local average is 1.0. The nearest neighbour pixels have the highest weighting in this average. This weighting is implicit in the use of surface fitting to remove larger scale variations. Those variations include sky background, calibration LED illumination and shutter effects.

By definition, the PRNU is a multiplicative effect. So the application of it as a correction involves simply dividing an image by the PRNU model.

Data header

Primary Header:

SIMPLE	file does conform to FITS standard
BITPIX	number of bits per data pixel
NAXIS	number of data axes
EXTEND	FITS dataset may contain extensions
FITS_DEF	FITS definition name
FITS_VER	FITS definition version
TIMESYS	Time scale of the time-related keywords
PLAN_ID	32-bit SOC Operation ID
BUNIT	Pixel data unit, e.g. ‘electrons’ or ‘adu’
OBASW	On board application software version: version.
DATE	UT date when this file was created
SOFTVERS	version of the simulator or version of the LE1
EXPTIME	Commanded integration time in seconds, e.g. 565
IMG_CAT	Data product category: SCIENCE, CALIB, TECHNICA
IMG_T1	values in {BIAS, DARK, FLAT, LINEARITY, CHARGE_INJECTION
IMG_T2	values in {LAMP, SKY, DOME, OTHER…} from SEQU
OBSMODE	Observation Mode (WIDE, DEEP, CALIBRATION)
OBSTYPE	DP technique (IMAGE, SPECTROIMAGE)
INSTRUME	VIS, or VISsim for simulations
TELESCOP	Telescope name: EUCLID
OBT_STA1	Integer, number of seconds of OBT (START_TIME)
OBT_STA2	Integer, number of milliseconds of OBT (START_TIME)
DATE-OBS	Inst. seq. start time in UTC
MJD-OBS	Inst. seq. start time in MJD
FIELDID	Field Id
OBS_ID	OSS_obsid
DITHOBS	OSS_inObsId
PTGID	OSS_pointingID
EXPNUM	Exposure Id in dither
TOTEXP	Total number of Exposures in the specific Point
INSTRMOD	VIS intrument mode: Science or Manual
COMPALGO	Science TM compression mode: NoCompression, Co
COMPPARA	Science TM compression parameters: pixels/block
RA	OSS_attEqLon
DEC	OSS_attEqLat
PA	OSS_attEqPosAngle
EQUINOX	Standard FK5 (years), e.g. 2000.
SEQID	VIS sequences as defined in EUCL-IFS-ICD-6-002
DATE-END	Inst. seq. end time in UTC
OBT_END1	Integer, number of seconds of OBT (VIS sequence)
OBT_END2	Integer, number of milliseconds of OBT (VIS sequence)
NOMCHAIN	VDGT2771
VSTART	Index of first readout line (starting at 0)
VEND	Index of last readout line + 1
ROECFGID	ROE configuration table ID
RSUSINID	Table version of RSU SINE table used in the RSU
RSUFRID	Table version of RSU FREQ table used in the RSU
RSUSFRID	Table version of RSU short FREQ table used in t
RSUCFSTA	Shutter unit configuration status: CLOSED_LOOP,
TP_STAT	Trap pumping status: off, parallel, serial, mul
CUSTATUS	Calibration unit status: On or Off
CI_STAT	Charge injection status: On or Off
CULEDDUR	If CU on: pulse duration in (s)
CULEDMSK	Indicates which LEDs are active. Bit0(LSB)=LED1
LED1RAW	LED1 current DAC value
LED1CURN	If LED1 on: nominal current (mA)
LED1FLUN	If nominal LED1 on: fluence (ADU)
LED1CURR	If LED1 on: redundant current (mA)
LED1FLUR	If redundant LED1 on: fluence (ADU)
LED2RAW	LED2 current DAC value
LED2CURN	If LED2 on: nominal current (mA)
LED2FLUN	If nominal LED2 on: fluence (ADU)
LED2CURR	If LED2 on: redundant current (mA)
LED2FLUR	If redundant LED2 on: fluence (ADU)
LED3RAW	LED3 current DAC value
LED3CURN	If LED3 on: nominal current (mA)
LED3FLUN	If nominal LED3 on: fluence (ADU)
LED3CURR	If LED3 on: redundant current (mA)
LED3FLUR	If redundant LED3 on: fluence (ADU)
LED4RAW	LED4 current DAC value
LED4CURN	If LED4 on: nominal current (mA)
LED4FLUN	If nominal LED4 on: fluence (ADU)
LED4CURR	If LED4 on: redundant current (mA)
LED4FLUR	If redundant LED4 on: fluence (ADU)
LED5RAW	LED5 current DAC value
LED5CURN	If LED5 on: nominal current (mA)
LED5FLUN	If nominal LED5 on: fluence (ADU)
LED5CURR	If LED5 on: redundant current (mA)
LED5FLUR	If redundant LED5 on: fluence (ADU)
LED6RAW	LED6 current DAC value
LED6CURN	If LED6 on: nominal current (mA)
LED6FLUN	If nominal LED6 on: fluence (ADU)
LED6CURR	If LED6 on: redundant current (mA)
LED6FLUR	If redundant LED6 on: fluence (ADU)
OBT_STA	OBT at start time
DATE-ENH	UTC of LE1 Enhancement
AUX_VERS	LE1 Enh. (AUX) Processor name & version
ELAT	OSS_attEclipLat
ELONG	OSS_attEclipLon
POS	OSS_attEclipPosAngle
ALPHA	OSS_alpha
BETA	OSS_beta
SAA	OSS_saa
PATCH_ID	OSS_obsPatchId
FOV_LAT1	OSS_fovLat1
FOV_LAT2	OSS_fovLat2
FOV_LAT3	OSS_fovLat3
FOV_LAT4	OSS_fovLat4
FOV_LON1	OSS_fovLon1
FOV_LON2	OSS_fovLon2
FOV_LON3	OSS_fovLon3
FOV_LON4	OSS_fovLon4
VS1T2043	VS1T2043
VS1T2050	VS1T2050
VS1T2020	VS1T2020
VS1T2021	VS1T2021
VS1T2028	VS1T2028
VS1T2029	VS1T2029
VS1T2036	VS1T2036
VS1T2037	VS1T2037
VS2T2043	VS2T2043
VS2T2050	VS2T2050
VS2T2020	VS2T2020
VS2T2021	VS2T2021
VS2T2028	VS2T2028
VS2T2029	VS2T2029
VS2T2036	VS2T2036
VS2T2037	VS2T2037
VS3T2043	VS3T2043
VS3T2050	VS3T2050
VS3T2020	VS3T2020
VS3T2021	VS3T2021
VS3T2028	VS3T2028
VS3T2029	VS3T2029
VS3T2036	VS3T2036
VS3T2037	VS3T2037
VS4T2043	VS4T2043
VS4T2050	VS4T2050
VS4T2020	VS4T2020
VS4T2021	VS4T2021
VS4T2028	VS4T2028
VS4T2029	VS4T2029
VS4T2036	VS4T2036
VS4T2037	VS4T2037
VS5T2043	VS5T2043
VS5T2050	VS5T2050
VS5T2020	VS5T2020
VS5T2021	VS5T2021
VS5T2028	VS5T2028
VS5T2029	VS5T2029
VS5T2036	VS5T2036
VS5T2037	VS5T2037
VS6T2043	VS6T2043
VS6T2050	VS6T2050
VS6T2020	VS6T2020
VS6T2021	VS6T2021
VS6T2028	VS6T2028
VS6T2029	VS6T2029
VS6T2036	VS6T2036
VS6T2037	VS6T2037
VS7T2043	VS7T2043
VS7T2050	VS7T2050
VS7T2020	VS7T2020
VS7T2021	VS7T2021
VS7T2028	VS7T2028
VS7T2029	VS7T2029
VS7T2036	VS7T2036
VS7T2037	VS7T2037
VS8T2043	VS8T2043
VS8T2050	VS8T2050
VS8T2020	VS8T2020
VS8T2021	VS8T2021
VS8T2028	VS8T2028
VS8T2029	VS8T2029
VS8T2036	VS8T2036
VS8T2037	VS8T2037
VS9T2043	VS9T2043
VS9T2050	VS9T2050
VS9T2020	VS9T2020
VS9T2021	VS9T2021
VS9T2028	VS9T2028
VS9T2029	VS9T2029
VS9T2036	VS9T2036
VS9T2037	VS9T2037
VSAT2043	VSAT2043
VSAT2050	VSAT2050
VSAT2020	VSAT2020
VSAT2021	VSAT2021
VSAT2028	VSAT2028
VSAT2029	VSAT2029
VSAT2036	VSAT2036
VSAT2037	VSAT2037
VSBT2043	VSBT2043
VSBT2050	VSBT2050
VSBT2020	VSBT2020
VSBT2021	VSBT2021
VSBT2028	VSBT2028
VSBT2029	VSBT2029
VSBT2036	VSBT2036
VSBT2037	VSBT2037
VSCT2043	VSCT2043
VSCT2050	VSCT2050
VSCT2020	VSCT2020
VSCT2021	VSCT2021
VSCT2028	VSCT2028
VSCT2029	VSCT2029
VSCT2036	VSCT2036
VSCT2037	VSCT2037
POS_X	OEM_x
POS_Y	OEM_y
POS_Z	OEM_z
VEL_X	OEM_vx
VEL_Y	OEM_vy
VEL_Z	OEM_vz
CALBLKID	OSS_obsType
CALBLKVR	OSS_variant
N_CCD
BIASSEC	Offset area relative to readout, 1-based
LEDID
FLUENCE

Extension Header:

XTENSION	IMAGE extension
BITPIX	number of bits per data pixel
NAXIS	number of data axes
NAXIS1	length of data axis 1
NAXIS2	length of data axis 2
PCOUNT	required keyword; must = 0
GCOUNT	required keyword; must = 1
EXTNAME
DETID	CCD-ID field from science TM (0-35)
CCDID	e.g. Detector ID, e.g. ‘0-0’, ‘1-1’ … ‘6-6’
QUADID	e.g. Quadrant ID, e.g. ‘E’, ‘F’, ‘G’ or ‘H’
ROEID	ROE ID: 1-12
ROECTV	ROE configuration table version
BUNIT	Pixel data unit, e.g. ‘electrons’ or ‘adu’
PRESCANX	number of serial prescan pixels, e.g 51
OVRSCANX	number of serial overscan pixels, e.g 29
OVRSCANY	number of parallel overscan pixels, e.g 20
EXPDUR1	Nominal/Short, nominal with CI, Flat: duration
EXPDUR2	Nominal/Short, nominal with CI, Flat: duration
WCSAXES	Number of axes in the WCS description. This key
CRVAL1	Right ascension at ref pixel
CRVAL2	Declination at ref pixel
CRPIX1	Reference pixel x coordinate
CRPIX2	Reference pixel y coordinate
CD1_1	Translation matrix element
CD1_2	Translation matrix element
CD2_1	Translation matrix element
CD2_2	Translation matrix element
CTYPE1	Coordinate 1 type
CTYPE2	Coordinate 2 type
CUNIT1	Physical units of CRVAL1
CUNIT2	Physical units of CRVAL2
RADESYS	Coordinate reference frame, e.g. ‘FK5’
CMPRTSCI	Quadrant image compression ratio obtained on-bo
GAIN
RDNOISE
RA
DEC
PA
EXPTIME
SATLEVEL	pixel saturation level in e-
SATURATE	pixel saturation level in ADU
BIAS_LVL
BIAS_RON
BIAS_TOP
BIAS_BTM
BIAS_LFT
BIAS_RGT
BZERO
BSCALE
STKCOUNT