Vis Stacked Frame Product¶
$SetSchemaPath vis/euc-vis-StackedFrame.xsd
Data product name¶
$PrintDataProductName
Data product custodian¶
$PrintDataProductCustodian
Name of the Schema file¶
$PrintSchemaFilename
Last Edited for DPDD Version¶
1.1
Processing Element(s) creating/using the data product¶
VIS_science_xml_out
Processing function using the data product¶
Proposed for inclusion in EAS/SAS¶
Yes
Data product elements¶
$PrintDataProductElements
Detailed description of the data product¶
The VIS PF provides stacked images which individual VIS dither is combined using SWarp. By default, the option COMBINE TYPE=CLIPPED is used (D. Gruen et al 2014).
The VIS processing function provides a Stackedframe product consisting of 3 FITS files by exposure: a stacked VIS image, and the corresponding Background map and Weight MAP.
A PSF is also computed as an internal product for SExtractor fitting like the spread model.
Calibrated VIS stacked image¶
The calibrated stacked image is a multiple extension FITS file with 3 extension : Science, RMS map, Flag map.
The tangent point (Calabretta & Greisen 2002) of the output image is computed by SWarp software with the option “CENTER_TYPE all”. Therefore, the size of this image and its tangent point is for the moment not pre-defined, and can vary based on the coverage of the input dithers. The output tangent point is approximately equal to the geometric average of the tangent point of the input images.
The input data products (SCI, RMS, and FLG) are resampled to constant pixel scale over the focal plane of 0.1” / pixel. The images are background subtracted with a sliding window using the following parameters BACK_SIZE=64 and BACK_FILTERSIZE=3.
SCI extension¶
The fluxes in each pixel of the SCI extension are rescaled to have a zero point of 23.9 AB magnitudes with an effective exposure time of 1s.
RMS extension¶
As for the calibrated VIS individual images, the RMS map contains standard deviation at each pixel in the corresponding Science image, expressed as the absolute standard deviation.
FLG extension¶
For the stacked images, the value of the Flagmap is 0 for good data, 1 otherwise. Flags are stored as eight-bit unsigned integers.
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 |
EQUINOX |
Mean equinox |
RADESYS |
Astrometric system |
CTYPE1 |
WCS projection type for this axis |
CUNIT1 |
Axis unit |
CRVAL1 |
World coordinate on this axis |
CRPIX1 |
Reference pixel on this axis |
CD1_1 |
Linear projection matrix |
CD1_2 |
Linear projection matrix |
CTYPE2 |
WCS projection type for this axis |
CUNIT2 |
Axis unit |
CRVAL2 |
World coordinate on this axis |
CRPIX2 |
Reference pixel on this axis |
CD2_1 |
Linear projection matrix |
CD2_2 |
Linear projection matrix |
EXPTIME |
Maximum equivalent exposure time (s) |
GAIN |
Maximum equivalent gain (e-/ADU) |
SATURATE |
Saturation Level (ADU) |
SOFTNAME |
The software that processed those data |
SOFTVERS |
Version of the software |
SOFTDATE |
Release date of the software |
SOFTAUTH |
Maintainer of the software |
SOFTINST |
Institute |
AUTHOR |
Who ran the software |
ORIGIN |
Where it was done |
DATE |
When it was started (GMT) |
COMBINET |
COMBINE_TYPE config parameter for SWarp |
RESAMPT1 |
RESAMPLING_TYPE config parameter |
CENTERT1 |
CENTER_TYPE config parameter |
PSCALET1 |
PIXELSCALE_TYPE config parameter |
RESAMPT2 |
RESAMPLING_TYPE config parameter |
CENTERT2 |
CENTER_TYPE config parameter |
PSCALET2 |
PIXELSCALE_TYPE config parameter |
OBS_ID |
OSS_obsid |
DITHOBS |
OSS_inObsId |
EXPNUM |
Exposure Id in dither |
MAGZEROP |
zero-point |
PHOT_ERR |
self calibration photometric error |
PHOTIRMS |
self calibration mag dispersion RMS |
APERCORR |
self calibration aperture correction MAG_50pix |
APCORRMS |
self calibration aperture correction rms error |
Extension Header |
|
|---|---|
XTENSION |
Image extension |
BITPIX |
number of bits per data pixel |
NAXIS |
number of data axes |
NAXIS1 |
Number of pixels along this axis |
NAXIS2 |
Number of pixels along this axis |
PCOUNT |
number of parameters |
GCOUNT |
number of groups |
EXTEND |
This file may contain FITS extensions |
EQUINOX |
Mean equinox |
RADESYS |
Astrometric system |
CTYPE1 |
WCS projection type for this axis |
CUNIT1 |
Axis unit |
CRVAL1 |
World coordinate on this axis |
CRPIX1 |
Reference pixel on this axis |
CD1_1 |
Linear projection matrix |
CD1_2 |
Linear projection matrix |
CTYPE2 |
WCS projection type for this axis |
CUNIT2 |
Axis unit |
CRVAL2 |
World coordinate on this axis |
CRPIX2 |
Reference pixel on this axis |
CD2_1 |
Linear projection matrix |
CD2_2 |
Linear projection matrix |
EXPTIME |
Maximum equivalent exposure time (s) |
GAIN |
Maximum equivalent gain (e-/ADU) |
SATURATE |
Saturation Level (ADU) |
SOFTNAME |
The software that processed those data |
SOFTVERS |
Version of the software |
SOFTDATE |
Release date of the software |
SOFTAUTH |
Maintainer of the software |
SOFTINST |
Institute |
AUTHOR |
Who ran the software |
ORIGIN |
Where it was done |
DATE |
When it was started (GMT) |
COMBINET |
COMBINE_TYPE config parameter for SWarp |
RESAMPT1 |
RESAMPLING_TYPE config parameter |
CENTERT1 |
CENTER_TYPE config parameter |
PSCALET1 |
PIXELSCALE_TYPE config parameter |
RESAMPT2 |
RESAMPLING_TYPE config parameter |
CENTERT2 |
CENTER_TYPE config parameter |
PSCALET2 |
PIXELSCALE_TYPE config parameter |
OBS_ID |
OSS_obsid |
DITHOBS |
OSS_inObsId |
EXPNUM |
Exposure Id in dither |
MAGZEROP |
zero-point |
PHOT_ERR |
self calibration photometric error |
PHOTIRMS |
self calibration mag dispersion RMS |
APERCORR |
self calibration aperture correction MAG_50pix |
APCORRMS |
self calibration aperture correction rms error |
EXTNAME |
Data type (SCI, RMS, or FLG) |
Weight Map¶
Primary Header |
|
|---|---|
SIMPLE |
This is a FITS file |
BITPIX |
|
NAXIS |
|
NAXIS1 |
Number of pixels along this axis |
NAXIS2 |
Number of pixels along this axis |
EXTEND |
This file may contain FITS extensions |
EQUINOX |
Mean equinox |
RADESYS |
Astrometric system |
CTYPE1 |
WCS projection type for this axis |
CUNIT1 |
Axis unit |
CRVAL1 |
World coordinate on this axis |
CRPIX1 |
Reference pixel on this axis |
CD1_1 |
Linear projection matrix |
CD1_2 |
Linear projection matrix |
CTYPE2 |
WCS projection type for this axis |
CUNIT2 |
Axis unit |
CRVAL2 |
World coordinate on this axis |
CRPIX2 |
Reference pixel on this axis |
CD2_1 |
Linear projection matrix |
CD2_2 |
Linear projection matrix |
EXPTIME |
Maximum equivalent exposure time (s) |
GAIN |
Maximum equivalent gain (e-/ADU) |
SATURATE |
Saturation Level (ADU) |
SOFTNAME |
The software that processed those data |
SOFTVERS |
Version of the software |
SOFTDATE |
Release date of the software |
SOFTAUTH |
Maintainer of the software |
SOFTINST |
Institute |
AUTHOR |
Who ran the software |
ORIGIN |
Where it was done |
DATE |
When it was started (GMT) |
COMBINET |
COMBINE_TYPE config parameter for SWarp |
RESAMPT1 |
RESAMPLING_TYPE config parameter |
CENTERT1 |
CENTER_TYPE config parameter |
PSCALET1 |
PIXELSCALE_TYPE config parameter |
RESAMPT2 |
RESAMPLING_TYPE config parameter |
CENTERT2 |
CENTER_TYPE config parameter |
PSCALET2 |
PIXELSCALE_TYPE config parameter |
Background Map¶
The background map delivered corespond to the background map from SExtractor.
Primary Header |
|
|---|---|
SIMPLE |
This is a FITS file |
BITPIX |
|
NAXIS |
|
NAXIS1 |
Number of pixels along this axis |
NAXIS2 |
Number of pixels along this axis |
EXTEND |
This file may contain FITS extensions |
EQUINOX |
Mean equinox |
RADESYS |
Astrometric system |
CTYPE1 |
WCS projection type for this axis |
CUNIT1 |
Axis unit |
CRVAL1 |
World coordinate on this axis |
CRPIX1 |
Reference pixel on this axis |
CD1_1 |
Linear projection matrix |
CD1_2 |
Linear projection matrix |
CTYPE2 |
WCS projection type for this axis |
CUNIT2 |
Axis unit |
CRVAL2 |
World coordinate on this axis |
CRPIX2 |
Reference pixel on this axis |
CD2_1 |
Linear projection matrix |
CD2_2 |
Linear projection matrix |
EXPTIME |
Maximum equivalent exposure time (s) |
GAIN |
Maximum equivalent gain (e-/ADU) |
SATURATE |
Saturation Level (ADU) |
SOFTNAME |
The software that processed those data |
SOFTVERS |
Version of the software |
SOFTDATE |
Release date of the software |
SOFTAUTH |
Maintainer of the software |
SOFTINST |
Institute |
AUTHOR |
Who ran the software |
ORIGIN |
Where it was done |
DATE |
When it was started (GMT) |
COMBINET |
COMBINE_TYPE config parameter for SWarp |
RESAMPT1 |
RESAMPLING_TYPE config parameter |
CENTERT1 |
CENTER_TYPE config parameter |
PSCALET1 |
PIXELSCALE_TYPE config parameter |
RESAMPT2 |
RESAMPLING_TYPE config parameter |
CENTERT2 |
CENTER_TYPE config parameter |
PSCALET2 |
PIXELSCALE_TYPE config parameter |
OBS_ID |
|
DITHOBS |
|
EXPNUM |
|
MAGZEROP |
zero-point |
PHOT_ERR |
self calibration photometric error |
PHOTIRMS |
self calibration mag dispersion RMS |
APERCORR |
self calibration aperture correction MAG_50pix |
APCORRMS |
self calibration aperture correction rms error |