M45 and Machholz on 8 January -- the Sky Cleared!!

Davoud wrote:
I would love to see other east-coast photos of Machholz and the
Pleiades. This is probably the best that I can do at my current skill
level. I don't know whether my inability to capture the comet's tails
is because of my lack of skill, or because the sky half-way between
Baltimore and Washington isn't black enough to support such an
exposure. http://www.davidillig.com/ast-m45-machholz050108.shtml.

Thanks,

Davoud
Sayf Connary kindly took time to reply:
Well, I don't pretend to know anything about anything...

I was born and raised in a coal patch. We weren't _expected_ to know
anything.

, but I think your
picture is still a good one. Maybe Pete Lawrence can chime in on this one.

Thanks.

Is that blueish haze around the Pleiades nebulosity? It almost looks
like someone took a blue highlighter marker and colored it in. :-)

The image is somewhat overcooked, but it contains no artificial
ingredients.

Davoud

--
usenet *at* davidillig dawt com

On Sun, 09 Jan 2005 12:06:55 +0000, Pete Lawrence
wrote:

On Sun, 09 Jan 2005 02:59:51 -0500, Michael McCulloch
wrote:

However, I ran one photo tonight at 3200 ASA for 400 seconds with my
10D and cannot see any ion tail. I think the ion tail has really faded
in brightness and the dust tail seems less defined.

Wow - no tail at ISO3200 for 400s! I'm quite surprised by that. What
optical arrangements were there on the front of the camera Michael?

I am surprised as well. I'm still playing with my photos from last
night taken Jan 9th around 4 UT (some 5 hours after your photo), but
so far none of them show any ion tail in the vicinity of the comet
head even in inverted grayscale.

Here is the one shot at 3200 ASA for 400s. I only took it to attempt
to discover the orientation of the ion tail in the frame so I could
maximize coverage in the fov:

http://gamesforone.com/stars/notail.jpg

There may be barely a hint of something at the 1 o'clock position but
the brightness and contrast of that image has been pushed to an
extreme.

My setup is a 105mm apo at f/6.2. The camera was at prime focus.

---
Michael McCulloch

On Sun, 09 Jan 2005 10:16:03 -0500, Michael McCulloch
wrote:

Wow - no tail at ISO3200 for 400s! I'm quite surprised by that. What
optical arrangements were there on the front of the camera Michael?

I am surprised as well. I'm still playing with my photos from last
night taken Jan 9th around 4 UT (some 5 hours after your photo), but
so far none of them show any ion tail in the vicinity of the comet
head even in inverted grayscale.

Here is the one shot at 3200 ASA for 400s. I only took it to attempt
to discover the orientation of the ion tail in the frame so I could
maximize coverage in the fov:

http://gamesforone.com/stars/notail.jpg

There may be barely a hint of something at the 1 o'clock position but
the brightness and contrast of that image has been pushed to an
extreme.

My setup is a 105mm apo at f/6.2. The camera was at prime focus.

My guess it that something's happened to turn the tail off Michael. A
number of other posts on other forums from Stateside imagers suggests
no tail either. My shot at 18h42m UT on the 8th,

http://www.digitalsky.org.uk/comets/...-08-18h42m.jpg

definitely shows a tail, albeit a faint one - which I've attributed to
the layer of thin cloud I was imaging through.

I wonder if the aurora producing solar activity has had an effect?

--
Pete
http://www.digitalsky.org.uk
Global Projects - http://www.globalobservers.net

:
I notice that your photo did capture the point-like nucleus. With
enough exposure time to capture the tail, that would have been much
over-exposed (as seen in other photos that do show the tail).

Indeed. I should have noted in my post that I did capture some faint
tail detail in a couple of longer exposures, but the resulting images,
whether taken individually or stacked, were not visually pleasing to
me.

The most important thing that I should have mentioned is that I am a
hobbyist, not a researcher. My sole objective is to produce
visually-pleasing images, whether I am making astrophotographs,
photographing nature, or making portraits.

With the above in mind, insofar as astrophotography is concerned, I
have to keep my expectations realistic because of my location. I
believe that I can improve my skill at processing astrophotographs, as
I have considerable experience in producing both commercial and
fine-art images in Photoshop. I live almost exactly half-way between
Baltimore and Washington, D.C., however, and at present I have some
doubts as to how deep I can go with an astrophotograph -- again keeping
in mind my sole objective of producing visually pleasing images.
Whether or not my object is achieved is, of course, in the eye of the
beholder.

I listen to constructive criticism, and I appreciate the fact that
people take time to visit my web site and criticize my work. Now I
gotta go and re-examine last night's comet images in "light" of the
criticism in this thread!

Thanks to all,

Davoud

--
usenet *at* davidillig dawt com

On Sun, 09 Jan 2005 15:27:21 +0000, Pete Lawrence
wrote:

My shot at 18h42m UT on the 8th,

http://www.digitalsky.org.uk/comets/...-08-18h42m.jpg

definitely shows a tail, albeit a faint one - which I've attributed to
the layer of thin cloud I was imaging through.

It appears to be correct orientation to be a trace of the ion tail in
your photo. The fov of my photo is more limited and at least in the
vicinity of the comet head the ion tail has almost disappeared. I
would have oriented the camera to capture more if I had been able to
see any hint of the tail at the time.

Here is one image taken by a 'expert-level' fellow in our local club:

http://www.mikefleenor.com/comet/macholz_1.htm

His setup barely captures the ion tail. In any case, it is quite
faint. Hopefully it will turn back on soon.

---
Michael McCulloch

Achim Schaller of the Black Forest Germany has the best shot yet.
Spaceweather.com
doesn't know how to select the best pics!

http://www.spaceweather.com/swpod200.../Schaller1.jpg

Sorry to be of no help whatsoever but....I'm using the link you provided to
your nice widefield shot of the comet to help friends in another news group
have a look see. And for that shot I thank you.

Best regards,
Bill
"Davoud" wrote in message
...
I would love to see other east-coast photos of Machholz and the
Pleiades. This is probably the best that I can do at my current skill
level. I don't know whether my inability to capture the comet's tails
is because of my lack of skill, or because the sky half-way between
Baltimore and Washington isn't black enough to support such an
exposure. http://www.davidillig.com/ast-m45-machholz050108.shtml.

Thanks,

Davoud

--
usenet *at* davidillig dawt com

Do you have any experience with film ISO's vs. digital and exposure times?

"MrNightguy" writes:

Achim Schaller of the Black Forest Germany has the best shot yet.
Spaceweather.com
doesn't know how to select the best pics!

http://www.spaceweather.com/swpod200.../Schaller1.jpg

Wow, this is one impressive shot, including the M45 nebulosity with
some details! I'll have to look for the limiting magnitude with XEphem
later today, definitely seems to be pretty good.

o you have any experience with film ISO's vs. digital and exposure times?


I do. About 5 to 7 years with hypered Kodak Pro 400 film by Lumicon, may be
150 rolls. The CCD is Starlight express SXV-H9C one shot color camera for a
year. I don't know how to count the number exposures because I make 20 at a
time and then combine them by either adding or averaging. A typical evening is
100 exposures and in '04 I was out 75 times. I live just North of
Philadelphia. To equate the two media is difficult, but here's my conclusions.
1. I think the CCD is faster by a factor of 2 to 4. 2. I usually take 20-2
min exposures totaling 40 minutes and average 16 of them. 3. I throw out the
ones with plane trails, which happens quit often. 4. Because of the larger
dynamic range of the CCD, I can photograph objects impossible with film. From
my home I could only get 15 Messier objects after 5 years. With the CCD I did
75 my first year. Problems with vignetting and sky glow is a thing of the
past. I'm not saying that my images are as good as those that show up in S&T,
I am saying that my CCD images are superior to my film images.
Hope this helps.