Image Customisation

Similarly to query(), the plot() method of a DataSet accepts various additional arguments depending on the kind of data that is being plotted.

When plotting an Image, two such arguments can be utilised: cmap and relative_axes.

Note

Calling open() automatically calls plot() if a figure has not already been generated. In this case, open() passes any additional keyword arguments to plot(). A new plot will also be generated if the keyword arguments passed to open() do not match those of the stored figure.

Changing the Colour Map

The cmap parameter sets the colour map of the plotted image:

1. viridis (default):

from ATK import query

ps_query = query("image", targets=2552928187080872832, survey="panstarrs", band="g", size=120, path="example_image_1.fits.gz")
ps_query.open(cmap="viridis")

2. grey:

ps_query.open(cmap="grey")

3. false_colour, which maps the wavelength of the image filter into a single RGB colour:

ps_query.open(cmap="false_colour")

Configuring Axes Coordinates

So far, all images have had coordinate axes that are defined relative to the image centre, i.e. relative_axes = True (default). To instead use absolute coordinates on the sky, pass ``relative_axes = False`:

ps_query.open(relative_axes=False)

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