from POSS2 made possible through the Digitized
Sky Survey. Other images and information about POSS2 may be
The M42 region was overexposed in POSS2 data. To solve this
problem, I created a composite using my prior image of the Great Nebula
from last year.
Size: about 8 degrees FOV
Distance: 1600 light years (Horsehead
Nebula, aka B33); 826 light years
(Alnitak- Zeta Orionis); 1165 light years (Sigma Orionis)
RA: 5h 40m 56s
Dec: -1 degrees 56' 21"
This represents a 198 subframe mosaic
that I assembled over a 2 week period using data from POSS2, as well as a
composite with my prior Great Nebula image.
I downloaded each subframe (60' x 60' each) and constructed the mosaic
in Photoshop, with intermittent use of Registar as needed.
Data from the red and blue plates were comprised of 99 subframes each,
resulting in a total of 198 individual frames to construct. I
assembled the red and blue mosaics separately, followed by combining
with my Bicolor
Processing technique to produce the final color image.
There were rare regions of the POSS2 subframes that contained small
gaps in the data, especially in the blue, or contained shadows of what
appeared to be the secondary mirror. I needed to "patch" these,
usually by obtaining an overlapping subframe that was slightly shifted
in RA and DEC. The highest
contains striking detail and reveals many beautiful reflection regions
that tend to go unnoticed compared to their more famous neighbors like
the Horsehead, M42, and M78.
note: Graphics on this website
may not be reproduced without author permission.
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