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view of about 4.5° square. We equipped an
SBIG STX-16803 camera with an Astrodon
3 nm Oxygen-III (OIII) filter, a 5 nm
Hydrogen-alpha (Hα) filter, and
Generation 2 RGB filters.
We took exposures from September
9–22, 2017, with the iTelescope.net site near
Siding Spring, New South Wales, Australia.
The panels are centered around
R.A. 5h21m59s, Dec. –68°20'12", allowing
for a 10 percent overlap among the panels.
That choice was a compromise between
attaining the largest coverage and provid-
ing enough overlap to register the images.
The calibrated and processed master
images from each of the four panels were
registered to a master image of the LMC


downloaded from the internet to act as a
template. Before using it, however, the tem-
plate was upsized to about 11,000 by 11,000
pixels to accommodate the side-by-side
4,000-by-4,000-pixel individual panels. All
the exposures were registered using the
program Registar.
We colorized the Hα data to a standard
red/magenta, following the same process
with the OIII data to transform it to
blue/green. We also took an extra step and
blended in a superluminance layer. It con-
tains both the Hα and OIII data, as well as
high-resolution data of many individual
deep-sky objects we’d previously taken
through a 20-inch PlaneWave CDK20 cor-
rected Dall-Kirkham ref lector. This helped

bring out more detail, especially in the
emission nebulae.
We sincerely want to thank Sakib
Rasool, who helped produce the original
annotations that formed a guide to the
labels included here.
The LMC lies 163,000 light-years away
and straddles the boundary between
Dorado and Mensa. It is the fourth-largest
galaxy in the Local Group, after the
Andromeda Galaxy (M31), the Milky Way,
and the Pinwheel Galaxy (M33).

Don Goldman and Josep Drudis are
observatory partners sharing equipment
at the iTelescope.net facility at Siding Spring,
New South Wales, Australia.

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