A small example to show use of spherical screen and composite maps

gistfile1.txt

#
# Use the helioprojective spherical screen to maintain the off-disk emission.
# Use composite map to overlay the two images.
#
import matplotlib.pyplot as plt
from sunpy.map import Map
from sunpy.coordinates import Helioprojective

eit = Map( "/Users/ireland/Data/jp2/TRACE/2008_11_12__08_36_22_272__SOHO_EIT_EIT_284.jp2")
trace = Map("/Users/ireland/Data/jp2/TRACE/2008_11_15__00_11_06_000__TRACE_TRACE_TRACE_195.jp2")

with Helioprojective.assume_spherical_screen(eit.observer_coordinate):
    #eit_screen = eit.reproject_to(eit.wcs)
    trace_screen = trace.reproject_to(eit.wcs)

comp = Map(eit, trace_screen, composite=True)

fig = plt.figure()
ax = plt.subplot(projection=eit)
comp.plot()
plt.show()