ASTRO: M74 colour

After restoring the G11 mount to working order I added some more luminance
to my recent M74 shot, so now I have 9 hours. Unfortunately seeing wasn't
good and there was gusty wind, so in spite of the better tracking of the G11
I didn't get better detail in the galaxy than with the LX200. Stars look
rounder though.
Colour was only 30 minutes per channel (plus 2x5 minutes for Halpha), which
turned out to be not nearly enough. I probably would need about the same
time for RGB as for L to get a decent colour image.

Taken from the middle of Berlin with an 8"LX200 and C8 on G11, both at
f/6.3, SXV-H9 camera, 108x5 minutes for L, 6x5 minutes for RGB with 2x5
minutes Halpha mixed into the red channel.

The new b/w image is at
http://ccd-astronomy.de/temp/M74-108x5gut.jpg
The colour version can be found at
http://ccd-astronomy.de/temp/M74colourgut.jpg

Stefan

"Stefan Lilge" wrote in message
...
After restoring the G11 mount to working order I added some more luminance
to my recent M74 shot, so now I have 9 hours. Unfortunately seeing wasn't
good and there was gusty wind, so in spite of the better tracking of the
G11
I didn't get better detail in the galaxy than with the LX200. Stars look
rounder though.
Colour was only 30 minutes per channel (plus 2x5 minutes for Halpha),
which
turned out to be not nearly enough. I probably would need about the same
time for RGB as for L to get a decent colour image.

Taken from the middle of Berlin with an 8"LX200 and C8 on G11, both at
f/6.3, SXV-H9 camera, 108x5 minutes for L, 6x5 minutes for RGB with 2x5
minutes Halpha mixed into the red channel.


neat!

color is very difficult when shooting from light polluted skies

Stefan Lilge wrote:

After restoring the G11 mount to working order I added some more
luminance to my recent M74 shot, so now I have 9 hours. Unfortunately
seeing wasn't good and there was gusty wind, so in spite of the better
tracking of the G11 I didn't get better detail in the galaxy than with
the LX200. Stars look rounder though.
Colour was only 30 minutes per channel (plus 2x5 minutes for Halpha),
which turned out to be not nearly enough. I probably would need about
the same time for RGB as for L to get a decent colour image.

Taken from the middle of Berlin with an 8"LX200 and C8 on G11, both at
f/6.3, SXV-H9 camera, 108x5 minutes for L, 6x5 minutes for RGB with 2x5
minutes Halpha mixed into the red channel.

The new b/w image is at
http://ccd-astronomy.de/temp/M74-108x5gut.jpg
The colour version can be found at
http://ccd-astronomy.de/temp/M74colourgut.jpg

Stefan
------------------------------------------------------------------------

Looks like my typical seeing. Glad to hear the mount has now passed the
acid test and you are back imaging. We still are deep in clouds here.
A little better seeing and you should bring out a few of the HII regions.

This was my first galaxy to try color on. First attempt came up with a
motor oil colored section. Still don't know why. Even today, using
those frames I get that odd color. I later redid it and got something
similar to your result.

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".

Richard Crisp wrote:

"Stefan Lilge" wrote in message
...

After restoring the G11 mount to working order I added some more luminance
to my recent M74 shot, so now I have 9 hours. Unfortunately seeing wasn't
good and there was gusty wind, so in spite of the better tracking of the
G11
I didn't get better detail in the galaxy than with the LX200. Stars look
rounder though.
Colour was only 30 minutes per channel (plus 2x5 minutes for Halpha),
which
turned out to be not nearly enough. I probably would need about the same
time for RGB as for L to get a decent colour image.

Taken from the middle of Berlin with an 8"LX200 and C8 on G11, both at
f/6.3, SXV-H9 camera, 108x5 minutes for L, 6x5 minutes for RGB with 2x5
minutes Halpha mixed into the red channel.



neat!

color is very difficult when shooting from light polluted skies


I can't do with with a half moon, let alone all of Berlin lighting up
the sky!

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".

On Sun, 21 Oct 2007 14:39:16 +0200, "Stefan Lilge"
wrote:

After restoring the G11 mount to working order I added some more luminance
to my recent M74 shot, so now I have 9 hours. Unfortunately seeing wasn't
good and there was gusty wind, so in spite of the better tracking of the G11
I didn't get better detail in the galaxy than with the LX200. Stars look
rounder though.
Colour was only 30 minutes per channel (plus 2x5 minutes for Halpha), which
turned out to be not nearly enough. I probably would need about the same
time for RGB as for L to get a decent colour image.

Taken from the middle of Berlin with an 8"LX200 and C8 on G11, both at
f/6.3, SXV-H9 camera, 108x5 minutes for L, 6x5 minutes for RGB with 2x5
minutes Halpha mixed into the red channel.

The new b/w image is at
http://ccd-astronomy.de/temp/M74-108x5gut.jpg
The colour version can be found at
http://ccd-astronomy.de/temp/M74colourgut.jpg

Stefan


Its a difficult object without much color no matter where one is.