ASTRO: M51 at f/10

I had a mostly clear night on March 23, but with a bright, almost full moon
I did not want to do any "serious" imaging and decided to try my 10" Meade
ACF (formerly known as ARC ;-) scope without a focal reducer. Even on a
bright target like M51 I did not get good signal in three hours. Actually
the image does not have better detail than my best shot with an 8" SCT at
f/6.3, but I still consider this image to be a success for the ACF scope as
I needed several tries with the 8" to get what I got with the 10" on the
first try.

This is also the first time I have used the mirror lock and guided with a
seperate guidescope. This was only half of a success as I had a shift of
about 2 pixels between frames, which led to some elongation of stars in RA.

I resized the image to 78% to make it look sharper and get rid of some
noise.

Taken from the middle of Berlin with a 10" Meade ARC at f/10 on a G11 mount,
SXV-H9 camera, 35x5 minutes.

The picture can also be found at
http://ccd-astronomy.de/temp/M51F10-35x5smallgut.jpg

Stefan

That is a good shot Stefan! nice.
Cann't wait for the 10" RCX400 imaging this one...(with the f/8 system..).

reg
Dirk


"Stefan Lilge" wrote in message
...
I had a mostly clear night on March 23, but with a bright, almost full moon
I did not want to do any "serious" imaging and decided to try my 10" Meade
ACF (formerly known as ARC ;-) scope without a focal reducer. Even on a
bright target like M51 I did not get good signal in three hours. Actually
the image does not have better detail than my best shot with an 8" SCT at
f/6.3, but I still consider this image to be a success for the ACF scope as
I needed several tries with the 8" to get what I got with the 10" on the
first try.

This is also the first time I have used the mirror lock and guided with a
seperate guidescope. This was only half of a success as I had a shift of
about 2 pixels between frames, which led to some elongation of stars in
RA.

I resized the image to 78% to make it look sharper and get rid of some
noise.

Taken from the middle of Berlin with a 10" Meade ARC at f/10 on a G11
mount, SXV-H9 camera, 35x5 minutes.

The picture can also be found at
http://ccd-astronomy.de/temp/M51F10-35x5smallgut.jpg

Stefan

up close and personal: wow!


"Stefan Lilge" wrote in message
...
I had a mostly clear night on March 23, but with a bright, almost full moon
I did not want to do any "serious" imaging and decided to try my 10" Meade
ACF (formerly known as ARC ;-) scope without a focal reducer. Even on a
bright target like M51 I did not get good signal in three hours. Actually
the image does not have better detail than my best shot with an 8" SCT at
f/6.3, but I still consider this image to be a success for the ACF scope as
I needed several tries with the 8" to get what I got with the 10" on the
first try.

This is also the first time I have used the mirror lock and guided with a
seperate guidescope. This was only half of a success as I had a shift of
about 2 pixels between frames, which led to some elongation of stars in
RA.

I resized the image to 78% to make it look sharper and get rid of some
noise.

Taken from the middle of Berlin with a 10" Meade ARC at f/10 on a G11
mount, SXV-H9 camera, 35x5 minutes.

The picture can also be found at
http://ccd-astronomy.de/temp/M51F10-35x5smallgut.jpg

Stefan

Wow! nice and sharp. Any color data planned??

Joe



"Stefan Lilge" wrote in message
...
I had a mostly clear night on March 23, but with a bright, almost full
moon
I did not want to do any "serious" imaging and decided to try my 10" Meade
ACF (formerly known as ARC ;-) scope without a focal reducer. Even on a
bright target like M51 I did not get good signal in three hours. Actually
the image does not have better detail than my best shot with an 8" SCT at
f/6.3, but I still consider this image to be a success for the ACF scope
as
I needed several tries with the 8" to get what I got with the 10" on the
first try.

This is also the first time I have used the mirror lock and guided with a
seperate guidescope. This was only half of a success as I had a shift of
about 2 pixels between frames, which led to some elongation of stars in
RA.

I resized the image to 78% to make it look sharper and get rid of some
noise.

Taken from the middle of Berlin with a 10" Meade ARC at f/10 on a G11
mount,
SXV-H9 camera, 35x5 minutes.

The picture can also be found at
http://ccd-astronomy.de/temp/M51F10-35x5smallgut.jpg

Stefan

Stefan Lilge wrote:

I had a mostly clear night on March 23, but with a bright, almost full moon
I did not want to do any "serious" imaging and decided to try my 10" Meade
ACF (formerly known as ARC ;-) scope without a focal reducer. Even on a
bright target like M51 I did not get good signal in three hours. Actually
the image does not have better detail than my best shot with an 8" SCT at
f/6.3, but I still consider this image to be a success for the ACF scope as
I needed several tries with the 8" to get what I got with the 10" on the
first try.

This is also the first time I have used the mirror lock and guided with a
seperate guidescope. This was only half of a success as I had a shift of
about 2 pixels between frames, which led to some elongation of stars in RA.

I resized the image to 78% to make it look sharper and get rid of some
noise.

Taken from the middle of Berlin with a 10" Meade ARC at f/10 on a G11 mount,
SXV-H9 camera, 35x5 minutes.

The picture can also be found at
http://ccd-astronomy.de/temp/M51F10-35x5smallgut.jpg

Stefan

You do need a lot more light at f/10 than f/5. Sometimes the mirror
lock arrives with unmeshed gears. That happened to me. I turned and
turnd the knob but nothing happened. When it is working it eventually
gets tight and a slip clutch releases sounding much like the one on a
car gasoline filler cap (at least one over here). If you aren't getting
that the mirror may not be locked. At least that's how mine works.

Image looks good in spite of the problem.

Rick


Rick

--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

Great job Stefan!

Stefan Lilge wrote:
I had a mostly clear night on March 23, but with a bright, almost full moon
I did not want to do any "serious" imaging and decided to try my 10" Meade
ACF (formerly known as ARC ;-) scope without a focal reducer. Even on a
bright target like M51 I did not get good signal in three hours. Actually
the image does not have better detail than my best shot with an 8" SCT at
f/6.3, but I still consider this image to be a success for the ACF scope as
I needed several tries with the 8" to get what I got with the 10" on the
first try.

This is also the first time I have used the mirror lock and guided with a
seperate guidescope. This was only half of a success as I had a shift of
about 2 pixels between frames, which led to some elongation of stars in RA.

I resized the image to 78% to make it look sharper and get rid of some
noise.

Taken from the middle of Berlin with a 10" Meade ARC at f/10 on a G11 mount,
SXV-H9 camera, 35x5 minutes.

The picture can also be found at
http://ccd-astronomy.de/temp/M51F10-35x5smallgut.jpg

Stefan




--
John N. Gretchen III
N5JNG NCS304
http://www.tisd.net/~jng3

"Stefan Lilge" wrote
....

........... Even on a bright target like M51 I did not get good signal in
three hours......

Looks good to me Stefan! I wish I could get seeing like that, but not here
under the jet stream nearly all of the time.

George N

Thanks George. Actually you got similar detail in your recent M51 shot
(which I just saw at "spacebanter.com", didn't make my newsserver) in just a
few minutes.

Stefan

"George Normandin" schrieb im Newsbeitrag
...

"Stefan Lilge" wrote
...

........... Even on a bright target like M51 I did not get good signal in
three hours......

Looks good to me Stefan! I wish I could get seeing like that, but not here
under the jet stream nearly all of the time.

George N

Hey Stefan.. Nice job at the long FL... Hope you get us some more close
views!

--
Regards, Doug W.
www.photonsfate.com
"Stefan Lilge" wrote in message
...
I had a mostly clear night on March 23, but with a bright, almost full moon
I did not want to do any "serious" imaging and decided to try my 10" Meade
ACF (formerly known as ARC ;-) scope without a focal reducer. Even on a
bright target like M51 I did not get good signal in three hours. Actually
the image does not have better detail than my best shot with an 8" SCT at
f/6.3, but I still consider this image to be a success for the ACF scope as
I needed several tries with the 8" to get what I got with the 10" on the
first try.

This is also the first time I have used the mirror lock and guided with a
seperate guidescope. This was only half of a success as I had a shift of
about 2 pixels between frames, which led to some elongation of stars in
RA.

I resized the image to 78% to make it look sharper and get rid of some
noise.

Taken from the middle of Berlin with a 10" Meade ARC at f/10 on a G11
mount, SXV-H9 camera, 35x5 minutes.

The picture can also be found at
http://ccd-astronomy.de/temp/M51F10-35x5smallgut.jpg

Stefan

"Stefan Lilge" wrote
...
Thanks George. Actually you got similar detail in your recent M51 shot
(which I just saw at "spacebanter.com", didn't make my newsserver) in just
a few minutes.


Stefan,

With our poor seeing the only advantage we have from a 20 is the reduced
exposure time. However, the seeing was not too good even for our standards
the night I did M-51.

George N