INS-DAS-26
This ICD supersedes the documents INT-DAS-2, JKT-DAS-1 and WHT-PDF-1.
UltraDAS produces exactly one FITS file per observation, where an "observation" is the set of integrations associated with one run number. Where two cameras are used in parallel (e.g. on ISIS blue and red arms) two observations are deemed to have taken place; two run numbers are issued and two FITS files are produced. Where one camera produces data from multiple readout-amplifiers, detectors or detector controllers, only one observation is deemed to have taken place; one run number is issued and all the pixels go into one FITS file.
Saving an observation to disc is an standard part of the observing commands such as run, bias etc. Depending on the camera in use, UltraDAS may wait to finish writing the file before the command returns or it may finish the writing during the next observation (in order to reduce the dead time between observations).
FITS files become available to the consumers only when they are complete and UltraDAS has finished with them. Consumers can write to the files after this but observatory policy is that they should not. UltraDAS does not read back its FITS files after it releases them. UltraDAS does not delete the FITS-files it outputs nor does it move them between directories; clearing old observations off the disc must be done by one of the consumer processes.
UltraDAS distinguishes archivable observations, scratch observations and glance observations. Archivable observations are to be recorded by the data manager. Scratch observations are not taken by the data manager but are recorded on disc for other consumers. Glance observations are held in memory and displayed but are not released to any consumers; if UltraDAS happens to write a glance observation to disc, it does not release the file.
Creation of a FITS file by UltraDAS takes time. UltraDAS typically starts writing the file at the start of the observation, but the consumer programmes may not depend on this as the behaviour may vary from camera to camera and between UltraDAS releases. The consumers must not attempt to use the file while UltraDAS is writing it. To enforce this, UltraDAS uses different names for the current and released observation-files. A consumer may use a released file as soon as it becomes visible in the directory structure. No file or record locking is used.
Consumers may detect the release of observation files in two ways:
Normally, there are no gaps in the sequence of run numbers. However, if
an observation fails, or is aborted by the user's command, then the run number
that it had been given will not be reused and there will be a gap. Run numbers
are issued to all runs, even glances, at the start of the observation: this
simplifies and unifies the software. Hence, taking and discarding glances
leaves gaps in the run-number sequence.
Within the data partitions, UltraDAS creates one directory per night of
observing, named for the date on which the night began; the name has the
format yyyymmdd. For example, the directory /obsdata/inta/19981112
would be used for observations from 1200hrs UTC on the 12th of November 1998
until 1200hrs on the following day.
All observations are stored in FITS files with image extensions, even if there is only one image per file. One image extension is produced for each contiguous raster in the output.
The primary HDU has this structure:
For the INT WFC, which has a shutter driven by the ICS, the integration timing is written in one of the packets in the primary HDU. For all other cameras, the integration timing is written in the extension HDUs.
Each image extension has this structure:
This use of image extensions was developed by NOAO for the cameras at KPNO and is felt to be a de-facto standard for multi-channel cameras [3]. However, the generalization to multiple windows was devised specifically for ING.
Some keywords are provided to match the perceived conventions of IRAF and the NOAO conventions; some are traditional at ING ("traditionally" means here "in the form generated by observing system s7 at the INT and JKT".) This means that some data are duplicated.
The INHERIT keyword comes from the STScI convention on inheritence of HDUs, as described in NASA's user guide to FITS [3]. The keyword, which takes the Boolean value T, states that the extension HDU to which it applies should inherit non-conflicting descriptors from the primary HDU. Thus, if one channel of the observation is extracted to a separate file, it carries with it all the relevant information from the primary HDU. To make this scheme work, there must not be an image following the primary HDU.
Each image has a primary and secondary world co-ordinate system (WCS). The primary WCS reserves space in the header in which data-reduction software may later write celestial coordinates. The secondary WCS defines the positions of images in linear coordinates in the focal plane. The WCS arrangements are described in the channel packet. There is no "WCS packet" covering the whole camera.
The pixels may be in any FITS format. Typically, CCD pixels are recorded as signed 16-bit integers (BITPIX=16, BZERO=32768, BSCALE not present). IR images are typically stored as 32-bit floating numbers (BITPIX=-32, BZERO not present, BSCALE not present).
At the time of writing, UltraDAS does not use other FITS extensions such as tables. It may do so in later releases.
The packets have formal names which form an agreement between the DAS,
ICS, TCS and CIA. Both the spelling and the case of the formal names must
be as given below.
Keyword | Values | Data type | Notes |
RUN | integer | Run number. | |
RUNSET | character | Format i:n:r - see below. | |
IRAFNAME | character | File name to be used by RFITS. |
The numbers in RUN are unique among observations at a given telescope, but the same number may apppear in the observations of all telescopes. The numbers reflect the order in which observations are started. Scratch and glance observations are given run numbers too, and these numbers come into play if a scratch or glance observation is later archived.
RUNSET describes the observation's relationship to a set of runs such as a dither sequence. The run is stated to be run i of a set of n runs, starting at run number r, these numbers being formatted in a string and separated by colons: e.g. '2:10:1234567' means second run of a sequence of 10, starting at run 1234567. Both i and n are counted from 1.
IRAFNAME takes the value r<n> where n is the run number
as in RUN.
Keyword | Values | Data type | Notes |
---|---|---|---|
SYSVER | character | Version
number of the observing system. |
|
ORIGIN | ING La Palma | As used at the WHT. | |
OBSERVAT | LAPALMA | Used by IRAF | |
OBSERVER | character | Typically, this contains the observer's initials. | |
PROPOSAL | character | This is the code for the PATT/CAT proposal. | |
OBJECT | character | If the observer has entered a title for the observation, it appears here. Otherwise, the name of the current target should be used, or the words ARC, BIAS, FLAT, SKY etc. as appropriate. | |
OBSTYPE | ARC, BIAS, DARK, FLASH, FLAT, FOCUS, GLANCE, PUPIL, SCRATCH, SKY, or TARGET | character | The type of observation, in the format understood by the archive and associated software at IOA, Cambridge. Upper case is mandatory. |
IMAGETYP | arc, bias, dark, flash, flat, focus, object, object, pupil, sky or object | character | The type of observation in the form preferred by IRAF. The value must match the value of OBSTYPE (see the note below). Lower case is mandatory. |
The lists of values for OBSTYPE and IMAGETYP are enumerations with the same ordering. If an observation takes, say, the second value (BIAS) for OPBSTYPE, then it also receives the second value (zero) for IMAGETYP. This causes the list of values for IMAGETYP to have some duplicate entries.
Keyword | JKT value | Data type | Meaning |
TELESCOP | JKT | character | Common name of telescope. |
LATITUDE | character | Latitude
of telescope corrected for polar motion. |
|
LONGITUD | character | Longitude
of telescope corrected for polar motion. |
|
HEIGHT | 2369 | real | [m] Height of observing floor above sea-level. |
SLATEL | LPO1.0 | character | The name for the telescope as understood by the library subroutine sla_OBS(). |
TELSTAT | character | TRACKING, GUIDING, etc. | |
CAT-NAME | character | The name of the target as stored in the target list. May be different from the name stored under OBJECT. | |
CAT-RA | character | Taken from the target list. In the format hh:mm:ss.ss. | |
CAT-DEC | character | Taken from the target list. In the format sdd:mm:ss.s. | |
CAT-EQUI | character | Equinox of the target's coordinates, taken from the target list. In the format Jnnnn.n, Bnnnn.n or A, where nnnn.n is in years AD. | |
CAT-EPOC | real | Epoch of the target's coordinates, taken from the target list. In years AD as a decimal fraction. | |
PM-RA | real | Proper motion in R.A. In seconds of time per year. | |
PM-DEC | real | Proper motion in dec. In seconds of arc per year. | |
PARALLAX | real | Half-annual parallax in seconds of arc. | |
RADVEL | real | [km/s]Heliocentric radial velocity of the target in. | |
RATRACK | real | Differential-tracking rate in arcsec/second in R.A. | |
DECTRACK | real | Differential-tracking rate in arcsec/second in dec. | |
RA | character | R.A. that the telescope is tracking. In the format hh:mm:ss.ss. | |
DEC | character | Dec. that the telescope is tracking. In the format sdd:mm:ss.s. | |
EQUINOX | real | Equinox of the coordinates in RA, DEC: a decimal number of years AD. Ideally, these coordinates should be given to the same equinox as CAT-RA and CAT-DEC. | |
RADECSYS | FK4, FK5, GAPPT |
character | Reference system for celestial coordinates. |
STSTART | character | Local sidereal time at the start of the observation. | |
ST | character | Same as STSTART | |
AZIMUTH | real | [deg] Mean azimuth of telescope during observation. | |
ZD | real | Mean zenith distance during observation. In degrees. | |
AIRMASS | real | Effective mean airmass during observation. | |
XAPOFF | real | Offset from nominal pointing in `x'. In degrees. | |
YAPOFF | real | Offset from nominal pointing in `y'. In degrees. | |
XAPNOM | real | [degrees] Offset of nominal pointing position from the rotator centre | |
YAPNOM | real | [degrees] Offset of nominal pointing position from the rotator centre. | |
ROTTRACK | T | True if the instrument platform maintained constant sky PA through the observation. | |
ROTSKYPA | real | Mean position of rotator during observation. In degrees. | |
PARANGLE | real | Parallactic angle. In degrees. | |
VIGNETTE | boolean | True if the mirror petals or the dome vignette the telescope's beam. | |
DOMEAZ | real | Mean azimuth of dome during observation. In degrees. | |
TELFOCUS | real | Position of telescope's focus drive. In metres. The sense of focus movement may vary between foci. | |
TEMPTUBE | real | Temperature of telescope tube in degrees Celsius. |
Keyword | INT value |
WHT value | Data type | Meaning |
TELESCOP | INT |
WHT | character | Common name of telescope. |
LATITUDE | |
character | Latitude of telescope corrected for polar motion | |
LONGITUD | |
character | Longitude of telescope corrected for polar motion | |
HEIGHT | 2348 |
2344 | real | [m] Height of observing floor above sea-level |
SLATEL | LPO2.5 |
LPO4.2 | character | The name for the telescope as understood by the library subroutine sla_OBS(). |
TELSTAT | character | Telescope status at start of observation, TRACKING, GUIDING, etc. | ||
MJD-OBS | real | [days] Modified Julian date at the start of the observation. | ||
JD | real | [days] Julian date at the start of the observation. | ||
CAT-NAME | character | The name of the target as stored in the target list. May be different from the name stored under OBJECT. | ||
CAT-RA | character | Taken from the target list. In the format hh:mm:ss.sss. | ||
CAT-DEC | character | Taken from the target list. In the format sdd:mm:ss.ss. | ||
CAT-EQUI | character | Equinox of the target's coordinates, taken from the target list. In the format Jnnnn.n, Bnnnn.n or A, where nnnn.n is in years AD. | ||
CAT-EPOC | real | [year] Epoch of the target's coordinates, taken from the target list. In years AD as a decimal fraction. | ||
PM-RA | real | [seconds/yr] Proper motion in R.A. | ||
PM-DEC | real | [arcsec/yr] Proper motion in Dec. | ||
PARALLAX | real | [arcsec] Annual parallax. | ||
RADVEL | real | [km/s] Heliocentric radial velocity of the target . | ||
RATRACK | real | [arcsec/s] Differential-tracking rate in R.A. | ||
DECTRACK | real | [arcsec/s] Differential-tracking rate in Dec. | ||
RA | character | R.A. that the telescope is tracking at the start of the observation. In the format hh:mm:ss.sss. | ||
DEC | character | Dec. that the telescope is tracking at the start of the observation. In the format sdd:mm:ss.ss. | ||
RADECSYS | FK4, FK5, GAPPT |
FK4, FK5, GAPPT | character | Reference system for celestial coordinates. GAPPT for Apparent coordinates. |
EQUINOX | real | For RADECSYS of FK4 or FK5: equinox of the coordinates in RA, DEC: a decimal number of years AD. Ideally, these coordinates should be given to the same equinox as CAT-RA and CAT-DEC. For RADECSYS of GAPPT: current date as fraction of year. | ||
UTOBS | character | Universal time at the start of the observation. | ||
STSTART | character | Local sidereal time at the start of the observation. | ||
ST | character | Same as STSTART. | ||
AZSTART | real | [deg] Azimuth of telescope at the start of the observation. | ||
AZEND | real | [deg] Azimuth of telescope at the end of the observation. | ||
ZDSTART | real | [deg] Zenith distance at the start of the observation. | ||
ZDEND | real | [deg] Zenith distance at the end of the observation. | ||
AMSTART | |
real | Airmass at the start of the observation. | |
AMEND | |
real | Airmass at the end of the observation. | |
AIRMASS | real | Effective mean airmass during observation. | ||
XAPOFF | real | [deg] Total aperture offset in 'x'. | ||
YAPOFF | real | [deg] Total aperture offset in 'y'. | ||
XAPNOM | real | [deg] Offset of nominal pointing position from the rotator centre. | ||
YAPNOM | real | [deg] Offset of nominal pointing position from the rotator centre. | ||
RAOFF | |
real | [arcsec] Positional offset parallel to RA (tangent plane). | |
DECOFF | |
real | [arcsec] Positional offset in Dec (tangent plane). | |
ROTTRACK | boolean | True if the instrument platform maintained constant sky PA through the observation. | ||
ROTSKYPA | real | [deg] Sky position angle at the start of the observation. | ||
MNTPASTA | |
real | [deg] Mount position angle at the start of the observation. | |
MNTPAEND | |
real | [deg] Mount position angle at the end of the observation. | |
PARANSTA | real | [deg] Parallactic angle at the start of the observation. | ||
PARANEND | |
real | [deg] Parallactic angle at the end of the observation. | |
VIGNETTE | |
boolean | True if the mirror petals or the dome vignette the telescope's beam. | |
DAZSTART | real | [deg] Azimuth of dome at the start of the observation. | ||
DAZEND | |
real | [deg] Azimuth of dome at the end of the observation. | |
AUTOMODE | |
character | State of guide loop: Unlocked, Locked or Suspended. | |
AUTOX | |
real | [pixel] x coord of autoguiding reference position. | |
AUTOY | |
real | [pixel] y coord of autoguiding reference position. | |
TELFOCUS | real | [m] Position of telescope's focus drive at the start of the observation. This is the virtual focus, uncorrected for temperature, elevation, etc. | ||
TEMPTUBE | real | [deg C] Temperature of telescope tube, ten minute running mean at the end of the observation. | ||
FSTATION | character | Focal station of observation. | ||
PLATESCA | real | [deg/m] Plate scale at the telescope focus. | ||
ACTELFOC | |
real | [m] Actual value of telescope focus encoder. | |
FOCUSTMP | |
real | [mm] Focus temperature correction. | |
FOCUSALT | |
real | [mm] Focus elevation correction. Currently only applied for WHT at Prime. | |
FOCUSFLT | |
real | [mm] Focus correction for filter. |
In the case of AIRMASS, the values are integrated every second to produce the effective mean airmass under the normal definition of that term.
EQUINOX should be read with RADECSYS to find out if coordinates are Besselian or Julian: FK4 coordinates are the Besselian ones. The old ING convetional of prefixing the EQUINOX value with J or B is dropped because it conflicts with the FITS standard.
The latitudes and longitudes of the telescopes can be found in the 1994 ING Observer's Guide.
This is the only packet in which the
otherwise-constant values differ between telescopes.
Keyword | Data type | Meaning |
AUTACQT | real | Integration time (in seconds) for acquisition. |
AUTGUIT | real | Integration time (in seconds) for guiding. |
AUTWINDO | integer | Number of autoguider window. |
AUTMODE | character | Name of autoguider mode. |
AUTXSEE | real | Mean FWHM (arcsec) of guide star, x-axis. |
AUTYSEE | real | Mean FWHM (arcsec) of guide star, y-axis. |
AUTXSRMS | real | RMS on FWHM (arcsec) of guide star, x-axis. |
AUTYSRMS | real | RMS on FWHM (arcsec) of guide star, y-axis. |
AUTMAGNI | real | Mean magnitude of guide star. |
AUTTRANS | real | RMS variation of magnitude of guide star. |
AUTMAGOF | real | Magnitude zero-point. |
AUTSTATN | integer | Number of readings used for statistical calculations. |
AUTOMODE | character | Mode of autoguiding. |
AUTOX | real | Guiding position on autoguider, x-axis. |
AUTOY | real | Guiding position on autoguider, y-axis. |
The mean and RMS value above are calculated
from the readings made between the start and end of each exposure.
Keyword | Value | Data type | Meaning |
INSTRUME | WFC | character | Name of instrument. |
WFFPOS |
integer | Position-number of deployed filter |
|
WFFBAND | character | Waveband of filter, e.g. "z". | |
WFFPSYS | character | Photometric system (e.g. Gunn). | |
WFFID | character | Identifier for individual filter (e.g 195). | |
SECPPIX | 0.333 | real | Image scale in arcseconds per pixel. |
Ideally, all headers would include the keyword SECPPIX.
However, the value is only known ahead of time for an instrument that has
no interchangeable optics that change the scale, has its own, unchanging detectors,
and is used at exactly one focus of one telescope. Only the INT WFC meets
these crtieria.
Keyword | Data type | Meaning |
TEMPOUT | real | Temperature outside the dome, in degrees C. |
TEMPDOME | real | Temperature inside the dome in degrees C. |
TEMPMIRR | real | Temperature of the primary mirror in degrees C. |
TEMPTUBE | real | Temperature of the telescope tube in degrees C. |
WSPEED | real | Wind speed in km/h |
WDIRECT | real | Wind direction in degrees east of north. |
HUMIDITY | real | Relative humidity as a percentage. |
PRESSURE | real | Atmospheric pressure in mbar. |
DUSTDENS | real | Atmospheric extinction in magnitudes. |
DEWPOINT | real | Dew-point temperature in degrees C. |
METMOLD | real | Time in seconds since measurements were obtained from the met. system. |
METTOLD | real | Time in seconds since measurements were obtained from the TCS |
Keyword | Value | Data type | Meaning |
INSTRUME | IDS | character | Name of instrument. |
SLITWID | real | Slit width in metres. | |
PSLITWID | real | Slit-width projected on detector in metres. | |
PAOFFSET | 0.0 | real | Slit PA - telescope's sky PA in degrees. |
SLTSKYPA | real | Position angle of slit on sky in degrees. | |
DEKKERID | character | Dekker-slide name. | |
DEKPOS | char | Name of Dekker-slide position. | |
BSCFILT | character | Name of colour filter in the beam below the slit. | |
BSNDFILT | character | Name of ND filter in the beam below the slit. | |
COLLNAME | character | Name of collimator. | |
COLLFOC | int | Collimator focus in encoder units. | |
HARTMANR | character | State of right Hartman-shutter: `OPEN' or `SHUT'. | |
HARTMANL | character | State of left Hartman-shutter: `OPEN' or `SHUT'. | |
CROSDISP | character | State of cross disperser: `IN' or `OUT'. | |
CLINESMM | int | Ruling density of cross disperser in lines per milimetre. | |
CDBLAZE | real | Blaze of cross disperser in Ângstroms. | |
CAMERA | character | Name of spectrograph camera: `235' or `500'. | |
GRATNAME | character | Name of grating. | |
GLINESMM | int | Ruling density of grating in lines per millimetre. | |
GRATBLAZE | real | Blaze of grating nm. | |
GRATANGL | real | Angle of grating in degrees. | |
GRATSHUT | character | State of grating shutter: `OPEN' or `SHUT'. | |
CENWAVE | real | Central wavelength of spectral image in nm. | |
DISPERSI | real | Spectra dispersion in nm of wavelength per mm of length projected on the detector. | |
FOSMIKER | real | Reading of FOS micrometer `R'. | |
FOSMIKEB | real | Reading of FOS micrometer `B'. | |
FOSMIKES | real | Reading of FOS micrometer `S'. |
Keyword | Data type | Meaning |
AGTVPOSX | real | TV's x-position in metres. |
AGTVPOSY | real | TV's y-position in metres. |
AGTVFILT | character | Name of TV filter. |
AGTVSHUT | character | State of TV shutter: `OPEN' or `SHUT'. |
AGPOSX | real | x-position of autoguider probe in metres. |
AGPOSY | real | y-position of autoguider probe in meters. |
ASNDFILT | character | Name of ND filter in the beam above the slit. |
ASCFILT | character | Name of colour filter in the beam below the slit. |
FLIPMPOS | character | Position of `flip' mirror: `IN" or `OUT'. |
AGARCLMP | character | Name of arc lamp in use (`NONE' if all lamps are off). |
AGARCND | character | Name of ND filter in front of arc lamp. |
COMPMPOS | character | Position of comparison mirror: `IN' or `OUT'. |
Keyword | Data type | Meaning |
AGTVPOSX | real | TV's x-position in metres. |
AGTVPOSY | real | TV's y-position in metres. |
AGTVFILT | character | Name of TV filter. |
AGTVSHUT | character | State of TV shutter: `OPEN' or `SHUT'. |
AGPOSR | real | r-position of autoguider probe in metres. |
AGPOST | real | theta-position of autoguider probe in degrees. |
ASNDFILT | character | Name of ND filter in the beam above the slit. |
ASCFILT | character | Name of colour filter in the beam above the slit. |
MAINMPOS | character | Name of mirror that directs the main beam. |
AGARCLMP | character | Name of arc lamp in use (`NONE' if all lamps are off). |
AGARCND | character | Name of ND filter in front of arc lamp. |
AGARCC | character | Name of colour filter in front of arc lamp. |
COMPMPOS | character | Position of comparison mirror: `IN' or `OUT'. |
Keyword | Values | Variable type | Meaning |
INSTRUME | ISIS | ||
CENWAVE | real | Central wavelength in nm. | |
GLINESMM | real | Ruling density of the grating in lines/mm. | |
DISPERSI | real | Spectra dispersion in nm of wavelength per mm of length projected on the detector. | |
ISIHWAVE | real | Position of half-wave polarizer. | |
ISIQWAVE | real | Position of quarter-wave polarizer. | |
DEKPOS | character | Name of dekker-slide position. | |
ISISLITU | LONG, MULTI or FIBRE | character | Name of slit-unit position: LONG, MULTI or FIBRE. |
SLITWID | real | Slit width in metres. | |
PAOFFSET | 90.2 | real | Slit pa. - mount p.a. in degrees. |
ISIFCP | FIELD-LENS, CALCITES, POLAROID or CLEAR | character | Choice of polarizer. |
ISIBFOLD | character | Position of blue fold. | |
ISIRFOLD | character | Position of red fold. | |
ISIFILTA | character | Name of filter A in ISIS arm. | |
ISISFILTB | character | Name of filter B in ISIS arm. | |
ISIHART | character | Configuration of hartmann shutter | |
COLFOC | character | Collimator focus in metres. | |
GRATNAME | character | Name of grating. | |
GRATANGL | character | Position of grating in degrees. | |
ISITIGHT | T or F | boolean | Is the spectrograph light tight? |
ISISDOOR | character | State of slit door. | |
ISIGDOOR | character | State of grating door. | |
ISILID | character | State of ISIS' lid. | |
ISICELL | character | State of grating clamps. |
Keyword | Values | Data type | Meaning |
INSTRUME | Prime Imaging |
character | Name of instrument (not included when PFIP used with AF2) |
PFADCSTA | real | Angle of ADC at start of observation in degrees. | |
PFADCEND | real | Angle of ADC at end of observation in degrees. | |
PFMFBAND | character | Passband of main-beam filter (e.g. V) from filter database. | |
PFMFPSYS | character | Photometric system of main-beam filter (e.g. Harris) from
filter database. |
|
PFMFNAME | character | Id-code of main-beam filter from filter database. | |
PFMFPOS | integer | Position of main filter-wheel. | |
PFAFBAND | character | Passband of autoguider filter from filter database. | |
PFAFPSYS | character | Photometric system of autoguider filter from filter database. | |
PFAFILT | character | Id-code of autoguider filter from filter database. |
|
PFAGX | real | x-position of autoguider in microns. | |
PFAGY | real | y-position of autoguider in microns. | |
PFTEMP | real | Temperature in centigrade |
|
PFHUM | real | Relative humidity as a percentage. |
|
PFAPOS |
integer |
Filter position of autoguider |
|
PFADCACT |
character |
State of ADC automatic updates |
|
PFAUTFOC |
character |
State of automatic telescope focus
updates |
|
PFFOCOFF |
real |
Last focus offset applied to telescope
to compensate for main filter optical characteristics |
The id-code of a filter is the unique and permanent ID of a particular
filter. It is not the position of a filter in the wheel.
Keyword |
Values |
DataType |
Meaning |
PFADCACT | character | State of ADC automatic updates | |
PFADCSTA | real | Angle of ADC at start of observation in degrees. | |
PFADCEND | real | Angle of ADC at end of observation in degrees. |
Keyword |
Values |
DataType |
Meaning |
AF2FLDDC | character | Field Dec as defined in CONFIGURE |
|
AF2FLDNM | character | Field name as defined in CONFIGURE |
|
AF2FLDRA | character | Field RA as defined in CONFIGURE |
|
AF2MODUL | character | AF2 Module ID |
|
AF2NDIS | integer | Total number of fibres disabled |
|
AF2NFIB | integer | Total number of fibres in this module | |
AF2NFID | integer | Total number of fiducial positions |
|
AF2NOBJ | integer | Total number of fibres configured on objects |
|
AF2NONPE | real | Non-perpendicularity term in distortion map |
|
AF2PLATE | real | Plate scale term in distortion map |
|
AF2RADIA | real | Radial distortion term in distortion map |
|
AF2RMS | integer | Overall positioning error RMS (microns) |
|
AF2TEMP | real | AF2 temperature |
Keyword |
Values |
DataType |
Meaning |
F<Fibre-number>CMNT | character | Comment | |
F<Fibre-number>DEC | character | Fibre Dec | |
F<Fibre-number>FIBT | integer | Fibre theta angle | |
F<Fibre-number>FIBX | integer | Fibre x position (microns) | |
F<Fibre-number>FIBY | integer | Fibre y position (microns) | |
F<Fibre-number>FPVX | integer | Fibre pivot x position (microns) | |
F<Fibre-number>FPVY | integer | Fibre pivot y position (microns) | |
F<Fibre-number>ID | integer | Object ID code | |
F<Fibre-number>MAGN | character | Object magnitude | |
F<Fibre-number>NAME | character | Object name | |
F<Fibre-number>PEX | integer | Fibre x position error (microns) | |
F<Fibre-number>PEY | integer | Fibre y position error (microns) | |
F<Fibre-number>RA | character | Fibre RA | |
F<Fibre-number>STAT | integer | Fibre status | |
F<Fibre-number>TYPE | character | Object type | |
F<Fibre-number>WT | real | Fibre weighting |
Keyword | Values | Variable type | Meaning |
INSTRUME | INGRIDCASS | character | "Name of Instrument" |
INGPSCAL | 12.9 | real | "INGRID Plate Scale (arcsec/mm)" |
INGPSPOS | 1-11 | integer | "Pupil Stop Position" |
INGPSNAM | <pupil stop name> | character | "Pupil Stop Name" The pupil stop names are defined in the EPICS configuration file "pupil.dat". |
INGF1POS | 1-11 | integer | "Filter 1 Position" |
INGF1NAM | <fwheel1 name> | character | "Filter 1 Name" The filter names are defined in the EPICS configuration file "fwheel1.dat". |
INGF2POS | 1-11 | integer | "Filter 2 Position" |
INGF2NAM | <fwheel1 name> | character | "Filter 2 Name" The filter names are defined in the EPICS configuration file "fwheel2.dat". |
INGPISTA | IN, OUT | character | "Pupil Imager Status" |
INGFOCUS | <focus_position> | character | "Focus (um)" |
Keyword | Values | Variable type | Meaning |
INGPSCAL | 2.17 | real | "INGRID Plate Scale (arcsec/mm)" |
INGPSPOS | 1-11 | integer | "Pupil Stop Position" |
INGPSNAM | <pupil stop name> | character | "Pupil Stop Name" The pupil stop names are defined in the EPICS configuration file "pupil.dat". |
INGF1POS | 1-11 | integer | "Filter 1 Position" |
INGF1NAM | <fwheel1 name> | character | "Filter 1 Name" The filter names are defined in the EPICS configuration file "fwheel1.dat". |
INGF2POS | 1-11 | integer | "Filter 2 Position" |
INGF2NAM | <fwheel1 name> | character | "Filter 2 Name" The filter names are defined in the EPICS configuration file "fwheel2.dat". |
INGPISTA | IN, OUT | character | "Pupil Imager Status" |
INGFOCUS | <focus_position> | character | "Focus (um)" |
The packet's formal name is usp.
Keyword | Values | Variable type | Meaning |
AOBENCH | FIXED, FLOATING or UNKNOWN | character | "State of NAOMI Optical Bench" |
AOSLSTA | NOT_INITIALISED, NOT_IN_POSITION, MOVING, SCIENCE, OSCA_PINHOLE, SPECTRAL_CALIB, WHITE_BRIGHT_CALIB, WHITE_DIM_CALIB, ERROR |
character | "State of NCU Slide" |
AOSLPOS | <current_position> | real | "Position of NCU Slide" |
AOLAMPHE | ON, OFF, or ERROR | character | "State of Helium Lamp within NCU" |
AOLAMPNE | ON, OFF, or ERROR | character | "State of Neon Lamp within NCU" |
AOLAMPNS | ON, OFF, or ERROR | character | "State of Naomi Simplex Lamp within NCU" |
AOLAMPOC | ON, OFF, WARMING_UP, COOLING_DOWN or ERROR | character | "State of Oasis Continuum Lamp within NCU" |
AOINTSP | <light_intensity> | integer | "Intensity of Spectral Iris" This value reflects the setting of the spectral iris within the NCU. Intensity will be represented in terms of a percentage (0-100) of the max possible light flux through the iris. |
AOINTNS | <light_intensity> | integer | "Intensity of Naomi Simplex Lamp Iris" This value reflects the setting of the white-dim iris within the NCU. Intensity will be represented in terms of a percentage (0-100) of the max possible light flux through the iris. |
AOINTOC | <light_intensity> | integer | "Intensity of Oasis Continuum Lamp Iris" This value reflects the setting of the white-bright iris within the NCU. Intensity will be represented in terms of a percentage (0-100) of the max possible light flux through the iris. |
AOADCDS | IN, OUT, MOVING, UNKNOWN or ERROR | character | "State of ADC Deployment System" |
AOADCAX | <correction_axis> | real | "Correction axis of ADC (degrees)"
Specifies the axis on which the ADC is providing its applied correction. The value will be stated in degrees, relative to some agreed reference position. |
AOADCCOR | <applied_correction> | real | "Degree of correction being applied by ADC"
Specifies the amount of correction being applied by the ADC in degrees. |
AOOFLAT | IN, OUT, MOVING, UNKNOWN or ERROR | character | "Deployment State of OASIS Flat" |
AOSFLAT | IN, OUT, MOVING, UNKNOWN or ERROR | character | "Deployment State of Simplexing Flat" |
AOFCORSTA | NOT_INITIALISED, NOT_IN_POSITION, MOVING, IN_POSITION, ERROR | character | "State of Filter Focus Correction Mechanism" |
AOFCORPOS | <current_position> | real | "Configuration of Filter Focus Correction Mechanism"
This field only returns valid data if the AOCORSTA field reports
IN_POSITION. |
Keyword |
Values | Data Type | Meaning |
AODCHPOS | <position_code> 0-10 |
integer | Position of dichroic changer: 0 = Parked; 1-10 =
Dichroic Positions 1-10. In the case of an error condition this field may contain negative values. Consult ING engineering for further information. |
AODCHNAM | <dichroic> eg "IR", "50/50", "#1", "#2", "#3", "#4", "#5". |
character | Name of the dichroic currently deployed by the dichroic
changer. In the cases of an error condition the field will contain a string saying "ERROR: <n>".Consult ING engineering for further information. |
Keyword |
Values | Data Type | Meaning |
INSTRUME | OASIS | character | "Name of instrument" |
OAPSCAL | Value to be determined ? | character | "OASIS Imaging Plate Scale (microns/arcsec)" |
OACONFIG | eg "LR10_33" | character | "Configuration Name" |
OAFOCPL | eg "clear aperture" | character | "Focal Plane Id" |
OAENLRGE | eg "clear aperture" | character | "Enlarger Id" |
OAFILTER | eg "oasis_MR_6,
7686-8452,7625-8537,5350,4900,-5.90" |
character | "Filter Id" |
OAIMAGER | eg "62mm (#1/2) , 2.1" | character | "Imaging Id" |
OASAMPLE | eg "145mm (#3/3) & 62mm (#2/2) " | character | "Sampler Id" |
OAWDGSL | eg "0" | character | "Wedge Slide Id" |
OAWDGAN | eg "14.510000" | character | "Wedge Angle" |
OAGRISM | eg "clear aperture" | character | "Grism Id" |
CAMERA_P | eg "-5.900000" | real | "Camera Position" |
OAFCLASS | eg 25 | integer | "File Class - used by Data Reduction" |
Keyword | EPM Process Variable Name | FITS Data Type | Collection Time | Description |
AOSYS | AoSystem | String | Write | This is the name of the adaptive optics unit. |
AODFM | DMtype | String | Write | The deformable mirror that is in use |
AOLENSLT | LensletName | String | Write | Name of lenslet used. |
AOWFILT | FilterNumber | Integer | Write | The filter number that was used. |
AOWEXP | WFSintegrationTime | Real | Write | The length of the WFS integration in millisecs. |
AOWBIN | WFSbinningMode | Integer | Write | Binning mode used by the WFS |
AOGAIN | GainGlobal | Real | Write | Global gain in centroid units |
AOWOFF | WFSoffsets | String | Write | WFS Offsets |
AOLOOP | NaomiLoopState | String | Write | AO loop state |
AOFOCOFF | FocusOffloadState | String | Write | Focus offload state |
AOOPTALG | OptAlgorithm | String | Write | AO optical algorithm |
AORECON | ReconAlgorithm | String | Write | Reconstructor algorithm |
AOCAMSYN | CameraSyncState | String | Write | Camera sync state |
AOGDX | PickoffPosnX | Real | Write | WFS pickoff x position (arcsec) |
AOGDY | PickoffPosnY | Real | Write | WFS pickoff y position (arcsec) |
AODMX | DMstagePosnX | Real | Write | DM stage x position (mm) |
AODMY | DMstagePosnY | Real | Write | DM stage y position (mm) |
AODMTMP1 | TempDM | Real | Write | DM temperature 1 (C) |
AODMTMP2 | Temp2 | Real | Write | DM temperature 2 (C) |
AOLAMP | NCUlampState | String | Write | NCU lamp state |
AOLMPINT | NCUlampIntensity | Real | Write | NCU lamp intensity |
AOMASK | NCUmaskState | String | Write | NCU mask state |
AOBSPLIT | NCUbeamsplitState | String | Write | NCU beamsplitter state |
AOSEGLIM | SegTiltLimit | Real | Write | Segment tip tilt limit |
Keyword | Data type | Meaning |
DATE-OBS | character | Date of observation in the FITS-approved format. |
UT | character | UTC of start of observation. In the format hh:mm:ss.s. |
UTSTART | character | UTC of start of observation. In the format hh:mm:ss.s. |
UT-MID | character | UTC at the middle of the exposure. In the format hh:mm:ss.s. |
ELAPSED | real | Length of exposure, including pauses, from end of clearing to start of readout. In seconds. |
DARKTIME | real | Same as ELAPSED. |
EXPOSED | real | Length of exposure, excluding pauses, from the first opening of the shutter to its final closing. In seconds. |
EXPTIME | real | Same as EXPOSED. |
DATE-OBS is the UT date and changes at 0000hrs UTC. It has the format yyyy-mm-dd.DATE-OBS and UTSTART must be derived from the same time-stamp. It is an error for UTSTART and DATE-OBS to refer to instants on opposite side of the date-change at midnight.
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DETECTOR | character | Name of the camera, e.g. EEV13. | |
CCDSPEED | FAST or SLOW | character | Name of the readout speed. Upper case is mandatory. |
CCDXBIN | real | Binning factor in the x or serial direction of the amplifier frame. | |
CCDYBIN | real | Binning factor in the y or parallel direction of the amplifier frame. | |
CCDSUM | character | Both binning factors, x given first, with no punctuation, e.g. "2 4" | |
NWINDOWS | integer | Number of readout windows in this observation. | |
CCDTEMP | real | [K] Cryostat temperature. | |
CCDTEMP2 |
real | [K] Monitor pt 1 temperature |
|
CCDTEMP2 |
real | [K] Monitor pt 2 temperature |
|
READMODE |
character | Readout mode |
|
STORMODE |
character | Store mode |
|
NUMREADS |
integer | Number of reads |
|
COAVERAG |
integer | Number of cycles coaveraged |
The binning is given in the amplifier frame because that's how the observing system applies the two factors. Some detectors (or detector segments) in a mosaic may have rotations and reflections between the amplifier frame and the detector frame in which all the pixels of the camera can be mosaicked together. The reflections don't affect the binning, but if there are relative rotations through an odd number of right angles, then the sense of binning differs between channels.
NWINDOWS is the number of readout windows of non-zero extent anywhere on
the camera in the current observation; it can change from run to run. A window
of zero extent (one or both size parameters set to zero) is "turned off"
and is ignored by the system. The camera may have windows of non-zero extent
defined, but may also have windowing disabled. When windowing is disabled,
NWINDOWS is set to zero.
NWINDOWS partly determines the number of image extensions in the observation
file.
Inside UltraDAS, the channel FITS-header packet describes the arrangement
of the data from one readout channel. The formal name of the packet is channel.
Keyword | Value | Data type | Meaning |
---|---|---|---|
IMAGEID | integer | Number of the image in the file. | |
DASCHAN | integer | Number of readout channel (1+). | |
WINNO | integer | Number of window (1+). | |
CHIPNAME | character | Name of detector chip. | |
CCDNAME | character | Same as CHIPNAME. | |
CCDTYPE | character | Type of detector, e.g. EEV42. | |
CCDXPIXE | real | [m] Size of pixels in the x axis of the CCD frame. | |
CCDYPIXE | real | [m] Size of pixels in the y axis of the CCD frame. | |
AMPNAME | character | Name of readout amplifier | |
GAIN | real | Gain of amplifier in electrons per ADU | |
READNOIS | real | Readout noise of amplifier in electrons | |
SATURATE | real | [ADU] Highest data value that is good data. | |
MAXBIAS | real | [ADU] Highest data value that is good data for a bias observation. | |
BIASSEC | character | Image section in image coordinates holding only bias values | |
TRIMSEC | character | Image section in image coordinates that excludes all bias areas and includes all illuminated areas | |
RTDATSEC |
character | Location in d-space for RTD |
|
CTYPE1 | X | character | Type of world coordinate for 1st axis in primary WCS. |
CTYPE2 | Y | character | Type of world coordinate for 2nd axis in primary WCS. |
CRPIX1 | real | Reference pixel on 1st axis in primary WCS. | |
CRPIX2 | real | Reference pixel on 2nd axis in primary WCS. | |
CRVAL1 | real | Value at reference pixel on 1st axis in primary WCS. | |
CRVAL2 | real | Value at reference pixel on 2nd axis in primary WCS. | |
CUNIT1 | pixel | character | Units of 1st axis in primary WCS. |
CUNIT2 | pixel | character | Units of 2nd axis in primary WCS. |
CD1_1 | real | Transformation matrix from image coordinates to primary WCS. | |
CD1_2 | real | Transformation matrix from image coordinates to primary WCS. | |
CD2_1 | real | Transformation matrix from image coordinates to primary WCS. | |
CD2_2 | real | Transformation matrix from image coordinates to primary WCS. | |
PROJP1 | real | Projection coefficient for primary WCS: linear term. | |
PROJP3 | real | Projection coefficient for primary WCS: cubic term. | |
PV1_1 | real | Projection coefficient for primary WCS: linear term. | |
PV1_2 | real | Projection coefficient for primary WCS: cubic term. | |
PV2_1 | real | Projection coefficient for primary WCS: linear term. | |
PV2_2 | real | Projection coefficient for primary WCS: cubic term. |
IMAGEID is an NOAO convention. It numbers the imagw extensions in the order
that they appear in the file, counting from one. This keyword is useful if
one image extension is extracted from its original file.
DASCHAN and WINNO are an ING convention that supports multiple readout-windows.
CCDNAME is the IRAFicated version of CHIPNAME. The two keywords take the same value. This value must identify a particular device, typically by reference to the silicon wafer on which it was made (e.g. A1708-2) rather than a cryostat (e.g. WFC) or a position in a mosaic (e.g. WFC-2).
RDNOISE is the IRAFicated version of READNOIS.
Each channel packet carries a world-coordinate system (WCS). The primary WCS is initially set by UltraDAS to "detector coordinates". That is:
The specification for the WFC packet was changed to use the encoding for main-beam filters suggested by Jim lewis for the Astronomical Data Centre, Cambridge. This encoding has been in use in the observing system for WFC for some months.
No specification exists for the JKT instrument-packets.
The details of the WHT instrument packets were copied from the packet list for the old (ADAM) WHT DAS [6]. That packet list gives different details for the telescope and observation packets but the INT's specification, which is new, is presumed to supersede this. The INT form of the headers is a better match to modern data-reduction software.
Some details of the ISIS, LDSS and TAURUS packets were altered to fit the
style adopted for the IDS packet.
The channel packet draw on the examples in NOAO's document
[3] but has more differences than similarities. The RRxx keywords are
specific to ING and replace NOAO's description of transformations. The WINxSWCn
and DISJOINT keywords do not appear in NOAO's header. NOAO appear to copy
into the extension header many data that apply equally to all channels: these
data are not present in the ING channel-packet, being covered in the primary
HDU.
Keyword | Values | Data type | Meaning |
---|---|---|---|
INSTRUME | TAURUS | character | Name of instrument. |
TAUCAMER | F/2 or F/4 | character | Name of spectrograph camera. |
TAUFRAT | 2.11 or 3.96 | real | Focal ratio of spectrograph camera. |
TAUSCALE | 23.25 or 12.40 | real | Image scale in arcsec/mm. |
TAUMASK | character | Name of aperture mask. | |
TAUFFILT | character | Name of focal-plane filter. | |
TAUIRIS | real | Diameter of iris in meters. | |
TAUPFILT | character | Name of pupil-plane filter. | |
TAUETALON | character | Name of etalon. | |
TAUFOCUS | real | Camera focus in metres. | |
TAUDOORS | character | State of access doors. | |
TAUTEMP1 | real | Temperature at focal plane in kelvin. | |
TAUTEMP2 | real | Temperature at etalon in kelvin. | |
TAUTEMP3 | real | External temperature in kelvin. | |
TAUPRES1 | real | Pressure at etalon cavity in mbar. | |
TAUPRES2 | real | External pressure in mbar. | |
TAUIVL | character | State of N2 inlet valve. | |
TAUOVL | character | State of N2 outlet valve. | |
CSCEXT | T or F | boolean | CS100 external control enabled? |
CSCINT | T or F | boolean | CS100 integration enabled? |
CSCGAIN | real | CS100 servo-gain. | |
CSCTICO | real | CS100 time-constant. | |
CSCLOOP | character | State of CS100 servo-loop. | |
CSCXOFF | real | CS100 x-offset. | |
CSCYOFF | real | CS100 y-offset. | |
CSCZOFF | real | CS100 z-offset. | |
CSCZSTAR | real | Start position for etalon scan. | |
CSCZSTEP | real | Step size for etalon scan. | |
CSCNSTEP | integer | Number of steps in etalon scan. | |
CSCRAMP | SINGLE or DOUBLE | character | Single or double-sized ramp? |
TAUFPSTE | integer | Number of detector frames per step. | |
PAOFFSET | real | Instrument p.a. - mount p.a. in degrees. |
Keyword | Values | Data type | Meaning |
INSTRUME | LDSS | character | Name of instrument. |
LDSMASK | character | Name of aperture mask. | |
LDSFILTE | character | Name of filter. | |
LDSGRISM | character | Name of grism. | |
LDSFOCUS | real | Camera focus in metres. | |
LDSDOORS | character | Status of access hatches. | |
LDSFRAT | real | Focal ratio of camera. | |
LDSSCALE | real | Image scale in arcsec/mm. | |
PAOFFSET | real | Instrument p.a. - mount p.a. in degrees. |