Pixel Scale Sensitive FITS Keywords
Several commands that scale the image pixel size (see list below) modify the spatial scale of the pixels. Maintaining the spatial image scale after these commands may require certain FITS header keywords to be adjusted accordi according to the operation.
FITS header Keywords in the table below are updated or added, as per the Status column. Note the number 1 or 2 following some keyword names. these are used to refer to axis 1 (columns increasing) or dimension 2 (rows increasing).
|
Keyword |
Origin |
Status |
|
CRPIX1 |
FITS Standard |
Modified if present |
|
CRPIX2 |
FITS Standard |
Modified if present |
|
CDELT1 |
FITS Standard |
Modified if present |
|
CDELT2 |
FITS Standard |
Modified if present |
|
CD Matrix (WCS) |
FITS Standard |
Modified** if present |
|
COL_BIN |
Early FITS consensus |
Added*, or Modified if present |
|
ROW_BIN |
Early FITS consensus |
Added*, or Modified if present |
|
SECPIX |
Early IRAF consensus |
Modified if present |
|
SECPIX1 |
Early IRAF consensus |
Modified if present |
|
SECPIX2 |
Early IRAF consensus |
Modified if present |
|
CCDBIN1 |
Origin unknown |
Modified if present |
|
CCDBIN2 |
Origin unknown |
Modified if present |
|
XPIXELSZ |
Camera control software |
Modified if present |
|
YPIXELSZ |
Camera control software |
Modified if present |
|
PSF-FWHM |
Mira |
Modified if present |
*The COL_BIN and ROW_BIN keywords are added by the Block Average Filter and Block Sum Filter.
The CD Matrix is present in images that have a World Coordinate System calibration.
World Coordinate System Keywords
Mira Pro x64 8.72 User's Guide, Copyright Ⓒ 2024 Mirametrics, Inc.
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