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Notes and Comments
The following is a list of nebulae which are only rarely photographed in color because of
their very low surface brightness. Only a small handfull of intrepid
astrophotographers attempt to image these challenging objects. (Reference: THE DEEP SKY
FIELD GUIDE to Uranometria 2000.0 by Cragin, Lucyk and Rappaport, Willmann-Bell, 1993):
Sh2-1: Emission + reflection nebula in Scorpius; 15 58.9
-26 09; size: 90' X 10'; near 6-Scorpii; photographic brightness 4-5 (i.e., very dim).
This very extended and faint reflection nebula is rarely photographed at all. I am unaware
of previous color images. The image is a digital composite of two one-hour
exposures on hypered Fuji SHG-400 with the 6 inch AP refractor.
Sh2-54/B95: On the Scutum/Serpens Cauda border this
large emission nebula is rarely, if ever, photographed in detail. This nebula is brightest
in the NE sector and to the east of the major area of emission is an interesting area of
dark nebulosity (B95): 18 18.0 -11 40, Photo. brightness 1-5; Located near the open
cluster NGC 6604. The image is a digital composite of two one-hour exposures on
hypered Fuji SHG-400 with the 6 inch f/7 AP refractor.
Sh2-88 & NGC6820/23: Located in Vulpecula near the
Dumbell Nebula, this pair of emission nebula are rarely photographed. Located in a very
rich starfield, NGC 6820 bears a striking resemblance to a miniature Rosette Nebula.
Sh2-88 consists of two bright knots 11' SE of center, and NGC6820 has a mottled appearance
with narrow, prominent dust lanes and absorption patches. Sh2-88 is located at 19 46.0 25
20 and measures 18' X 6', and NGC6820 is located at 19 43.1 23 17 and measures 40' X 30'.
Photo. brightness of both nebulae is 3-4. The image is a digital composite of
two one-hour exposures on un-hypered Kodak PPF Pro 400 with the 6 inch f/7 AP refractor.
Sh2-132: This overlooked, but surprisingly
bright,emission nebula is located in a very rich starfield on the Cepheus/Lacerta border
(22 18.7 56 08). Measuring 35' X 20' the NE sector is considerably higher in brightness.
This image is a digital composite of two 60-minute exposures on hypered Kodak PPF Pro 400
taken with the Astrophysics 6 inch f/7 refractor.
Sh2-129 & vdB140: Located in Cepheus at 21 11.8 59 57
(110' X 100')/ 21 17.5 58 36 (12' X 10'); Sh2-129 is an extremely faint emission nebula
with a photo. brightness of only 5. It is very annular in appearance and is brightest in
the NW and NE sectors with many small absorption patches. vdB140 is a small
knot of reflection nebulosity near a mag 6.4 star. I have not seen a prior image of these
two nebulae in color. The image is a digital composite of two one-hour exposures on
hypered Fuji SHG-400 with the 6 inch f/7 AP refractor.
Sh2-157: Located in the same photographic field as NGC7635
(Bubble Nebula) and M52, this rarely seen emission nebula covers a large area on the
border between Cepheus and Cassiopeia near the galactic star cluster NGC 7510. This nebula
lies about 2 degrees SW of the Bubble Nebula,
at 23 16.1 60 02, and covers nearly one degree of sky. Note also in this enhanced image
how much more extended the nebulosity around the Bubble nebula really is. This is not
appreciated in more familiar photographs of this object which represent a much smaller
field of view. The image is a digital composite of three 60-min.
exposures on hypered Fuji SHG400 with the 6 inch f/7 AP refractor.
Sh2-205: Measuring 100' X 30' and straddling the
Camelopardalis/Perseus border at 03 56.1 53 12, this extremely faint (photo. brightness 5)
and uniformly diffuse emission nebula pushes the copy-to-Vericolor enhancement technique
to its limit. Superior results are obtained using digital techniques. This
image is a digital composite of two 60-min. exposures on hypered Fuji SHG400 with the
6 inch f/7 AP refractor. Special techniques in Picture Window 2.0 using the
FILTER transformation of inverted (negative) images were necessary to get the optimum
enhancement of this faint nebula (See Digital
Techniques).
IC 353/1995: Overshadowed by the Pleiades, which
are immediately to the SW of this extremeley faint patch of reflection nebulosity,
IC353/1995 are rarely photographed, let alone in color. Measuring 180' X 30', this
gossamer web of nebulosity is a real challenge. It is not clear if this nebula is
associated with M-45. The image is a digital composite of four 50-minute
exposures on hypered 120 format Kodak PPF Pro 400 film.
vdB14/15: Located at 03 30 59 30, in Camelopardalis
near the Cassiopeia border, these two reflection nebula are never seen photographed in
color. Measuring only 20' X 10' they are located just east of the more familiar I.C.1848.
The final image is a digital composite of two 60-minute exposures on hypered 120
format Fuji SHG-400 with the 6 inch f/7 AP refractor.
IC 2118: A challenging object to photograph in color, the
Witch Head Nebula is located in Eridanus near Rigel on the border with Orion (05 6.9 -07
13). Bearing a striking resemblance to it's namesake, this extended (180' X 60') diffuse
nebula is catalogued as SNR-R, an unusual BLUE, reflection supernova remnant, which is
thought to be illuminated by Rigel. The brightest part is 70' ENE of 65 Eridani. The
final image is a digital composite of three 50-min. exposures on hypered Kodak PPF Pro 400
with the 6 inch f/7 AP refractor..
Sh2-264: This
is an extremely dim emission nebula and is one of the most challenging objects I
have ever photographed. Only digital enhancement was able to extract the image off
of the negatives. Special techniques in Picture Window 2.0 using
the FILTER transformation of negative (inverse) images was necessary (See Digital Techniques). Traditional darkroom enhancement
methods were unsuccessful. The nebula lies in far northern Orion at 05 35 +10 and
measures 270'X240'. Photo brightness 4-5. The final image is a digital
composite of two 60-minute exposures on hypered 120 format Kodak PPF Pro 400 film.
I.C. 348: This
extremely faint reflection nebulosity is another of the most difficult objects that I have
photographed. Traditional darkroom enhancement techniques were unsuccessful.
Optimal enhancement of the image required special digital techniques in Picture
Window 2.0 using the FILTER transformation of the negative (inverse) of the
digitized images (See Digital Techniques).
The nebula lies in Perseus near the border with Taurus at 03 44.5 +32 17. Photo
brightness 2-5. Interestingly, Uranometria shows the nebula as being very
small. However W. Tirion's Sky Atlas 2000 shows it to be much more
extended as evidenced in the photograph here. The final image is a digital
composite of two 60-minute exposures on 120 format Kodak PPF Pro 400 film.
Nebulosity in Corona Australis:
This image includes the very dim IC 4812 (19 01 -37 04), a reflection nebulosity
which is bright on blue but very faint on red survey plates and the high surface
brightness reflection nebulae NGC 6726/27 (19 01 -36 53) which surround two bright
stars and are illuminated by the variable star TY Corona Australis. Also in the
field is the extended dark nebula Barnard 157 as well as the globular cluster NGC
6723. Special digital techniques were necessary to bring out the full extent of
the very extended and faint nebulosity seen in the enhanced image (See Digital Techniques). This
is a challenging field to photograph from the latitude of my site (36 degrees N).
The image is a digital composite of two 60-minute exposures on hypered 120
format Kodak PPF Pro 400 film.
There are many other nebulae imaged on this Web-Site which represent
real challenges to the amateur astrophotographer which have been photographed in color by
professionals, particulary David Malin, as well as by a very few number of amateurs.These
include the beautiful emission nebulae NGC 7822 & Ced214
on the Cepheus/Cassiopeia border, the extended reflection nebulae IC4592
and nearby IC4601 in Scorpius, the spectacular
yellow reflection nebula IC4606 around Antares in
Scorpius (challenging to photograph at longer focal lengths), the huge region of emission
nebulosity near M6 in Scorpius and the beautiful pair of
reflection nebulae, NGC6589/90 , embedded in the faint
patch of emission nebulosity, IC1283/84, located just S of
M24 in Sagittarius.
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