Reference Files¶
The saturation
step uses a SATURATION reference file.
SATURATION Reference File¶
- REFTYPE:
SATURATION
- Data model:
SaturationRefModel
The SATURATION reference file contains pixel-by-pixel saturation threshold values.
Reference Selection Keywords for SATURATION¶
CRDS selects appropriate SATURATION references based on the following metadata attributes. All attributes used for file selection are required.
Instrument |
Keywords |
---|---|
WFI |
instrument, detector, date, time |
Standard ASDF metadata¶
The following table lists the attributes that are required to be present in all reference files. The first column shows the attribute in the ASDF reference file headers, which is the same as the name within the data model meta tree (second column). The second column gives the roman data model name for each attribute, which is useful when using data models in creating and populating a new reference file.
Attribute |
Fully Qualified Path |
---|---|
author |
model.meta.author |
model_type |
model.meta.model_type |
date |
model.meta.date |
description |
model.meta.description |
instrument |
model.meta.instrument.name |
reftype |
model.meta.reftype |
telescope |
model.meta.telescope |
useafter |
model.meta.useafter |
NOTE: More information on standard required attributes can be found here: Standard ASDF metadata
Type Specific Keywords for SATURATION¶
In addition to the standard reference file keywords listed above, the following keywords are required in SATURATION reference files, because they are used as CRDS selectors (see Reference Selection Keywords for SATURATION):
Keyword |
Data Model Name |
Instrument |
---|---|---|
detector |
model.meta.instrument.detector |
WFI |
Reference File Format¶
SATURATION reference files are ASDF format, with two data objects. The format and content of the file is as follows:
Data |
Object Type |
Dimensions |
Data type |
---|---|---|---|
data |
NDArray |
4096 x 4096 |
float32 |
dq |
NDArray |
4096 x 4096 |
uint32 |
The values in the data
array give the saturation threshold in units of DN
for each pixel.
The ASDF file contains two data arrays.