Editing the colormap and normalization of a Map

How to edit the display of a map.

import matplotlib
import matplotlib.colors as colors
import matplotlib.pyplot as plt

import sunpy.map
from sunpy.data.sample import AIA_171_IMAGE

We start with the sample data.

aiamap = sunpy.map.Map(AIA_171_IMAGE)

All plot settings for a map are stored in the plot_settings attribute. How a Map is displayed is determined by its colormap, which sets the colors , and the normalization, which sets how data values are translated to colors. Let’s replace the colormap and normalization.

aiamap.plot_settings['cmap'] = matplotlib.colormaps['Greys_r']
aiamap.plot_settings['norm'] = colors.LogNorm(100, aiamap.max())

To see all of the colormaps sunpy provides see sunpy.visualization.colormaps. Matplotlib provides a number of colormaps and normalizations. For more advanced normalizations see astropy.visualization.

fig = plt.figure()
ax = fig.add_subplot(projection=aiamap)
aiamap.plot(axes=ax)
plt.colorbar()
plt.show()

🏷 Tags: Map, AIA, Visualization