M42 The Great Orion Nebula
for full sized image)
Size: 85' x 60'
RA: 5h 35.3m
Dec: -5° 23'
The large glowing object in this
photograph is the Great Nebula in Orion. Also known as M42, this nebula and its
smaller companion to the north, M43, were cataloged by the 18th century comet
hunter, Charles Messier. These nebulas are fluorescent clouds of hydrogen gas
and dust excited by the ultraviolet-rich light of nearby blue-hot stars.
M42 is about 26 light-years across, and is
located only 1625 light years from us. It is practically in our own celestial
From a moderately dark site, M42 can be seen
with the naked eye as a misty patch of light in the sword of Orion. Beautiful
in binoculars, this bright nebula explodes with detail in amateur-sized
image was Santa Barbara Instrument Group's "Image of the
Month" for February 2001
Takahashi FSQ-106N f/5 4-element fluorite refractor
II German Equatorial Mount
Barbara Instrument Group ST-8E NABG CCD camera (1530 x 1020 pixels, 9 x 9mm, monochromatic, 16 bit, 13.8 x 9.2mm array)
color filter wheel with IR-blocking red, green and blue dichroic filters
Saturday, November 25, 2000
Joshua Tree National Park, CA
Approx. 3500', OAT +37F.
exposure time: 60 minutes. (4x5 minutes red, 4x5 min. green, and 4x5 min
Stacking: Green luminance behind RGB tricolor image. 60 minutes of deep
red, Hydrogen-alpha filtered exposure was shot but not used in final
composition. (I felt the green channel had better contrast and produced a
more interesting composition than I could achieve with the H-a luminance
Dark and flat cal, mean (not median) combining and DDP (on luminance) with
MaxIm. LRGB stacking, final level adjustments,
color balance, blooming repairs/reconstruction, crop and security with