Description¶
Overview¶
The FITS generator is used to convert data from several different
types of ground test data to DMS Level1b format data. This format is
described in the document DMS Level 1 and 2 Data Product Design -
JWST-STScI-002111
by Daryl Swade. The code uses a collection of
templates that govern the population of Level 1b header keyword values
from the data in the input file headers, with different templates for
different file types. The FITS generator will transform the input data
(in detector coordinates) to the DMS coordinate system, where all of the
imaging data has the same parity as the sky and very similar orientations.
Input details¶
To run the FITS generator, a ‘proposal’ file is required. There should be only one proposal file per directory, and it should have a name like
ddddd.prop
where d stands for a decimal digit. This file gives the names of each input FITS datafile, whether a subarray needs to be extracted from it and the exposure type (EXP_TYPE), as well as the relationship between the files from an operational viewpoint (i.e. Observation, Visit, ParallelSequenceID, Activity, Exposure, Detector). The file has a structure similar to XML with nested groups:
<Proposal title="MIRI FM IMG_OPT_01_FOV">
<Observation>
<Visit>
<VisitGroup>
<ParallelSequenceID>
<Activity>
<Exposure>
<Detector>
<base>MIRFM1T00012942_1_493_SE_2011-07-13T10h45m00.fits</base>
<subarray></subarray>
<exp_type>MIR_IMAGE</exp_type>
</Detector>
</Exposure>
</Activity>
</ParallelSequenceID>
</VisitGroup>
</Visit>
</Observation>
</Proposal>
Each nest can be repeated as needed. The <Detector></Detector> tags
contain the information for each input/output file, with the input
file name inside the <base>
tags, the name of the subarray to
be extracted within the <subarray>
tag, and the exposure
type within the <exp_type>
tag.
The files within the <base>
tag should be in the same directory
as the proposal file.
The input FITS files can be from any of several different sources:
MIRI VM2 testing
MIRI FM testing
NIRSPEC FM testing
NIRSPEC IPS Simulator
NIRCAM NCONT testing (detector only)
NIRCAM FM testing
NIRISS CV testing
FGS CV testing
Most data that has been taken using the FITSWriter tool can be successfully converted to Level 1b format.