Observing Report (UHC with 6" F5)

I went outside and setup the StarHOC 6" F5 Newtonian on CG-5 (old model
with aluminum legs). Now that the moon's out of the way for a few hours it
was time for some early evening star gazing.

First up, Jupiter. Still light outside and there wasn't any point looking at
anything else except the first star I could find to dial in the collimation.
Made out the equatorial belts and temperate zones with minor banding north
and south. Checking the Juplet Java applet after the fact I see that the GRS
was in transit, but I didn't see it in the eyepiece. Magnifications: 120x
and 166x; Filters tried: Celestron Polarizing and Blue 80A. The polarizing
filter was worthwhile when the sky was still light, but as it darkened I
pulled it and tried the blue. The blue actually helped with the contrast of
the north and south temperate zones, as well as darkening up the equatorial
belts. No more detail was visible, but there was an overall contrast
improvement on the large features.

Next up, M22, a favorite, as are the other large globulars. There are many
small globulars that are better served by larger apertures and higher
powers, but the likes of M22 and M13 are easy targets in a 6" scope at both
60x and 120x even in mag 5 skies.

Since the sky was now as dark as it was going to get, I moved on to M8, the
Lagoon Nebula. Visible as a bright patch against the gray light polluted
background, it was time to put the UHC to the test in a 6" scope. There was
no disappointment with the filter. Swapping back and forth between 60x
unfiltered and 42x filtered, there was no doubt that the UHC made the nebula
appear _much_ brighter against the background sky.

From there I moved up to M20, the Trifid Nebula with the UHC in place at
42x. A much harder target to see under the conditions than M8, but still
made visible with the UHC where it was virtually invisible without. Averted
vision helped of course with the filter in place, and hinted at the dark
lanes that give the Trifid its signature look.

On to M17, again better with filter than without. Clearly visible as both
it's namesakes Check Mark Nebula and Swan Nebula. This object has a dark
"spot" that stands out as an obvious patch darker than the background sky
and the nebulous cloud, which is what makes the nebula appear to have a
swan's neck.

The next object is one that I've never had much success with, M16, the Eagle
Nebula. However, my observing skill appears to continue to improve as this
object using averted vision with the UHC was clearly nebulous around the
open cluster with which it is intermingled. No Eagle was visible, nor any
detail really. Just the nebulosity around the open cluster.

As promised in the other post on filters, Cygnus was now in a prime position
for an attempt at the Veil. Moving the UHC from the 18mm eyepiece to the
30mm to increase the field of view, the western portion of the Veil (The
Cirrus Nebula) that passes nearby star 52 Cygni was invisible without the
filter and obvious with, even without averted vision. It didn't take much
searching around for the eastern portion of the Veil (The Network Nebula) to
pop into view with the filter in place. I forgot to check for this portion
of the nebula without the filter, but for sure the filter made the western
portion appear where it was otherwise not visible.

After that I swung the scope around to the west and took a long look at M13,
but first I wanted to see if I could find M5. I was successful, but as I
stated previously this is one of the small globulars that benefits from a
large aperture and higer power. Then it was back to M22 while it was clear
of the tree tops, finishing up with the Wild Duck cluster M11.

All in all a great night and reaffirmation that a 6" F5 Newtonian is a fun
and capable scope, and that a couple hours of observing is a great way to
spend an evening.

Steve Paul
42.6N 71.6W

All in all a great night and reaffirmation that a 6" F5 Newtonian is a fun
and capable scope, and that a couple hours of observing is a great way to
spend an evening.


Another target that I enjoy in a 6" is M76 - the Little Dumbbell Nebula. At
least in our club, it is not an often observed object and yet it looks very
good in a 6". Surprising to me, I have never tried our UHC on it, but I bet
it would respond well and I will definitely try it the next chance I get. In
case you don't know about it, David Knisely's article on filters at
http://www.cloudynights.com/item.php?item_id=1520 is excellent.

Dennis

"Dennis Woos" wrote in message
...
All in all a great night and reaffirmation that a 6" F5 Newtonian is a
fun and capable scope, and that a couple hours of observing is a great
way to spend an evening.


Another target that I enjoy in a 6" is M76 - the Little Dumbbell Nebula.
At least in our club, it is not an often observed object and yet it looks
very good in a 6". Surprising to me, I have never tried our UHC on it, but
I bet it would respond well and I will definitely try it the next chance I
get. In case you don't know about it, David Knisely's article on filters
at http://www.cloudynights.com/item.php?item_id=1520 is excellent.

Dennis

Thanks for the link. Even without the filter data, it serves as a good list
of objects to observe. :-)

-Steve

On Sep 2, 8:53 pm, "Steve Paul" wrote:

(. . .snip)
As promised in the other post on filters, Cygnus was now in a prime position
for an attempt at the Veil. Moving the UHC from the 18mm eyepiece to the
30mm to increase the field of view, the western portion of the Veil (The
Cirrus Nebula) that passes nearby star 52 Cygni was invisible without the
filter and obvious with, even without averted vision. It didn't take much
searching around for the eastern portion of the Veil (The Network Nebula) to
pop into view with the filter in place. I forgot to check for this portion
of the nebula without the filter, but for sure the filter made the western
portion appear where it was otherwise not visible.

After reading the above portion of your excellent observing report I
found myself wondering about your NELM. After a brief 'look back' I
found a reference to a magnitude 5 sky which made everything more
understandable. Last night I considered observing the Veil myself.
IIRC I can just fit both the eastern and western portions into the
same FOV if I use a 2" 40mm wide-field eyepiece with my 13cm f/6
refractor. Under a dark sky (without any filters) I've also seen the
smaller patch of nebulosity between the northern extremities of the
two major arcs. Perhaps tonight I'll take a look. I have a 2" O-III
that I could use to enhance the nebulosity a bit more . . .

(. . . snip)
All in all a great night and reaffirmation that a 6" F5 Newtonian is a fun
and capable scope, and that a couple hours of observing is a great way to
spend an evening.

Indeed! The 6" f/5 used to be considered "optimal" as a rich (or
richest) field telescope when used with a suitable eyepiece. Once
upon a time I was in the market for a pair of 6" f/5 achromats. I
wanted to build a pair of 6-inch binoculars for comet hunting . . .

Bill Greer
To sketch is to see.