Late Summer Image from the Swamp

All,

Everything is almost dried out now from the wet spring and summer g
Took a few nights worth of data on the Pelican in Ha.

12 x 30 minutes FSQ106N, STL11000M and 6nm Ha Filter. Guided with the
253mm RC lol

http://www.celestial-images.com/Imag...x1800s-Ha.html

Moon was present during most of this and I still need more data to
smooth the background out a bit.

Comments welcomed.

Regards

Bill

"William R. Mattil" wrote

12 x 30 minutes FSQ106N, STL11000M and 6nm Ha Filter. Guided with the
253mm RC lol

http://www.celestial-images.com/Imag...x1800s-Ha.html

Pretty amazing for a 4", Bill.

On Wed, 3 Oct 2007 14:46:00 -0700, "Howard Lester"
wrote:

Pretty amazing for a 4", Bill.

It's a beautiful image. In my eyes, only B&W really does justice to
these wide field objects.

A good 4" scope is capable of more resolution than this camera can
capture at this focal length. What's remarkable isn't the telescope, but
the patience of the imager to deal with the very long exposure time
required by such a small aperture.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

"Chris L Peterson" wrote

It's a beautiful image. In my eyes, only B&W really does justice to
these wide field objects.

Now that you mention it... it does seem that a B&W image shows more subtle
tonal gradations than most color images. Besides, since we can only see the
nebulae in B&W (except in rare cases), B&W images resemble what we really
see -- whereas color does not.

Howard Lester wrote:
"William R. Mattil" wrote

12 x 30 minutes FSQ106N, STL11000M and 6nm Ha Filter. Guided with the
253mm RC lol

http://www.celestial-images.com/Imag...x1800s-Ha.html

Pretty amazing for a 4", Bill.



Thanks Howard. I always find it surprising that Summer images take a lot
more exposure time to equal those taken in the Winter. As such I still
think this image needs more data. I was running the camera at -12C and
could have gone colder but I'm limited on space for all the calibration
frames on that computer. And 22 Meg per image still eats up a lot of space.

Anyway I've noticed this phenomenon with film and always assumed it was
an emulsion thing (Remember cold cameras ?) But obviously the
atmospheric conditions play a major role too.


Regards

Bill

Chris L Peterson wrote:
On Wed, 3 Oct 2007 14:46:00 -0700, "Howard Lester"
wrote:


It's a beautiful image. In my eyes, only B&W really does justice to
these wide field objects.

Thanks Chris.


A good 4" scope is capable of more resolution than this camera can
capture at this focal length.

That is absolutely true. 3.5 arc sec per pixel isn't a great match. The
same camera on a 253mm f/6 is 1 arc sec per pixel which is in the sweet
spot and the images look smoother to me.


What's remarkable isn't the telescope, but
the patience of the imager to deal with the very long exposure time
required by such a small aperture.

Awww come on ! Computers ! Remember ? For the most part the data
collection was automated. I got a three hour nap both nights and only
woke up to close up the observatory. This used to be a much larger
problem in the bad old days g

Regards

Bill

good optics - stunning patience and skills. congrats!

"William R. Mattil" wrote:

All,

Everything is almost dried out now from the wet spring and summer g
Took a few nights worth of data on the Pelican in Ha.

12 x 30 minutes FSQ106N, STL11000M and 6nm Ha Filter. Guided with the
253mm RC lol

http://www.celestial-images.com/Imag...x1800s-Ha.html

Moon was present during most of this and I still need more data to
smooth the background out a bit.

Comments welcomed.

Regards

Bill

On Wed, 03 Oct 2007 22:39:32 -0500, "William R. Mattil"
wrote:

Awww come on ! Computers ! Remember ? For the most part the data
collection was automated. I got a three hour nap both nights and only
woke up to close up the observatory. This used to be a much larger
problem in the bad old days g

Yeah, me too. Got to love automation. But the reality is that things
still aren't perfect, and the longer you image, the greater the chance
that something will go wrong. Still, I'd rather get a good night's sleep
and find out in the morning that I wasted a few imaging hours than to
exhaust myself by nursing a camera all night and then find out a few
days later- when the film is processed- that something didn't work. That
was truly the bad old days!

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Howard Lester wrote:
"Chris L Peterson" wrote

It's a beautiful image. In my eyes, only B&W really does justice to
these wide field objects.

I'm starting to miss B&W myself. I think this period in astronomical
history is going to be looked back upon sort as we do the late 60's: the
time of bright garish astronomical colors. Personally, I'm getting
tired of bright pink nebulae. :-)

To my eye there is an odd wavy background noise to this image, oriented
at about a 45 degree angle, particularly near the bottom. What caused this?

Greg

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

SkyTools: http://www.skyhound.com/cs.html
Observing: http://www.skyhound.com/sh/skyhound.html
Comets: http://comets.skyhound.com

To reply take out your eye

Greg Crinklaw wrote:

To my eye there is an odd wavy background noise to this image, oriented
at about a 45 degree angle, particularly near the bottom. What caused
this?

Hi Greg,

This was taken from a light polluted location with a moon present. So it
is quite likely that it's residual gradient from that.

Regards

Bill