This has always
been a great test object for me, a bright scattered open cluster
with galaxies hiding amongst the stars. The cluster is huge,
and only the center is recorded here in this 1 degree wide field
with the 10 inch.
of the same data are presented. The first is a conventional process
which shows nice stars and colors and is not stretched out too
The second image
has had a steep non linear curve applied to bring up the faintest
stars and faint 16th magnitude and fainter galaxies.
Finally, a negative
image with some annotations to identify the brightest galaxies.