Footprint Format#

Load sky footprints for instrument field-of-view visualization.

Overview#

The Footprint format is used for importing sky region footprints that represent instrument fields of view, observing apertures, or other spatial overlays. Footprints are displayed as overlays on images and can be used to plan observations or visualize coverage.

Usage#

import jdaviz
from regions import Regions

jd = jdaviz.show()

# Load a footprint from a region file
jd.load('instrument_fov.reg', format='Footprint')

# Or load a regions object with a custom label
regions = Regions.read('aperture.reg')
jd.load(regions, format='Footprint', footprint_label='JWST NIRCam')

Data Requirements#

The data should be spatial regions in sky coordinates:

  • Region types: Any region supported by the regions package (circles, rectangles, polygons, etc.)

  • Coordinate system: Must have sky coordinates (not pixel coordinates) that can be converted to pixel coordinates using the image WCS

  • Format: Single Region or Regions collection

Supported File Formats#

  • DS9 region files (.reg)

  • FITS region files (.fits)

  • Python objects: Region or Regions

Footprint Label#

When importing a footprint, you can specify a custom label: .. code-block:: python

jd.load(‘fov.reg’, format=’Footprint’, footprint_label=’Instrument FOV’)

If no label is provided, the default label ‘default’ will be used. This label specifies the name of the overlay layer that represents the Footprint region which can be modified in the Footprints plugin.

UI Access#

See Also#

  • Footprints - Footprints plugin for visualizing and managing footprints