Ballard Loc: Grass Valley, California

I finally received the parts to do some LRGB deep sky shots. For my first try I went back to my old friend M51. The sky was pretty bad with peak seeing going down to ~3-4 arc seconds (a lot of twinkle in the stars). The RMS on the guiding was not great but OK ~1.5 arc second, there were also thin high clouds, a first quarter moon as well as a layer of smoke from a "Controlled" burn a few miles away to deal with. But I was anxious to give LRGB deep sky a try so I went for it anyway. Considering the sky conditions the image came out better than I expected. The color is a bit off since I didn't go through the color calibration process yet but the image does have have less color noise and more detail than my previous DSLR image taken on a good night. I still need to learn a lot more on processing these types of images and using the camera.(These old CCDs are difficult to focus with ~10 sec download time between each test).
This image was made with 12, 5 minute subs for each filter (total exposure time ~4 hours minus a couple of subs that were not up to snuff). I also used Dark frames, Bias frames and Flat frames for each filter. I ran the camera a 0 degrees Celsius.

The equipment used was:
Used SBIG 11002 monochrome camera with Filter Wheel
Astrodon LRGB filters
Meade LX200 16 inch Schmidt-Cassegrain telescope.
Astrodon MOAG - for offaxis guiding
Starlight express Lodestar X2 - for the guide camera.
Optec TCF Leo focuser for focusing (This really helped since when you use the Mirror lock on the Meade it changes the focus slightly, but if you don't the focus will drift in less than 1 hour. With the TCF Leo attached I would use the telescope focus, then lock the mirror and the re-adjust the focus with with the mirror lock left engaged. Still a very tedious process with bad seeing and the long download from the CCD).
Mount Astrophysics 1600GTO

Software used
ASCOM platform for device control interface to programs.
Astro - Physics APCC - and associated ASCOM driver for mount control.
PHD - for guiding
Sky-X to tell the telescope where to go.
Pixinsight for processing the Image
SBig Control - to control the filter wheel and camera.

The next step will be to take a bunch of HA subs and learn how to integrate that into the image
All questions, comments and suggestions are welcome.

LRGB image of M51 the Whirlpool Galaxy

(Download)

bwana Loc: Bergen, Alberta, Canada

Pretty decent results!

As for Ha subs, simply add them into the Red channel then play with the amount of Red channel until you're happy with the end result.

bwa

bwa

optic Loc: Southwestern United States

Well, Ballard, next steps notwithstanding, I'd say you've done justice to M51 (!)

rmorrison1116 Loc: Near Valley Forge, Pennsylvania

Nice photo...

WJShaheen Loc: Gold Canyon, AZ

Excellent detail. Well done.

Question - Re: "I also used Dark frames, Bias frames and Flat frames for each filter.". I understand why you would need Flats for each filter. But why Darks and Bias frames, since the scope is covered or the shutter closed?

Also, since all of your exposures are the same (5 min.) you really don't need separate bias frames. The Bias signal is included in the Dark frame. Bias frames are needed when you have different exposure times and need to scale your Dark frames.

Just trying to save you some time and effort.

Again, beautiful.

Bill in Gold Canyon, AZ

MWojton Loc: Yardley, PA

Phenomenal shot! I just stare at it wondering if there is "life" somewhere in there.

Ballard Loc: Grass Valley, California

Thanks for checking out the image and for the method to add in HA.

Ballard Loc: Grass Valley, California

Hi optic
Thanks for checking out the image and for the comment.

Ballard Loc: Grass Valley, California

Hi rmorrison
Thanks for viewing the image and for the comment.

Ballard Loc: Grass Valley, California

Hi Bill in Gold Canyon
Thanks for checking out the image and for the comment. Note: I worded the sentence poorly. I should have said
"I used the same Dark and Bias frames and separate flats frames for processing the individual subs for each filter set".
Note: I also used the best sub from the set of luminance images as the reference image for stacking each set of subs for each filter. This made it a lot easier particularly since I had a meridian flip after the red exposures which had the M51 off by ~ 1 arc minute for the green and blue exposures (as well as 180 degree flip).

Ballard Loc: Grass Valley, California

Hi MWojton
Thanks checking out the image of M51 and for the comment. I would guess that life is probably common throughout the universe. I expect wherever it can form it will form.
For what it is worth in the spring of 1981 I was outside as dusk was coming to an end and I noticed a "satellite" coming out of the earths terminator (shadow) moving from east to west. I then noticed another "satellite" moving from the west to the east, they crossed paths directly over head and immediately the one moving from west to east did a 180 degree change in direction in ~1 sec and got directly behind the one moving from east to west and followed it over the western horizon. If indeed they where moving at low earth orbit speed (17,500 MPH) then the "satellite" that originally was moving from west to east performed a 35,000 MPH change in velocity (acceleration) in ~1 sec. That would work out to ~1600G acceleration. The only way to undergo that type of acceleration and survive would be to generate a uniform gravitational field so every molecule feels the same acceleration (like being in free fall which fells weightless). Since gravity is a bending of space time, you would need a method to bend space time on demand which I doubt that we know how to do yet.

WJShaheen Loc: Gold Canyon, AZ

Great!

stepping beyond Loc: usa eastcoast

Ballard you pulled alot out on m51, awesome job ! Processing this is a real bugger.

Ballard Loc: Grass Valley, California

Hi stepping beyond
Thanks for checking out the image of M51 and for the comment. I expect that adding some HA and perhaps some more subs to get a better signal to noise ratio will improve the shot. I also expect to learn more on how to best take and process these types of images.

stepping beyond Loc: usa eastcoast

Ballard ,I'll tell ya that getting the signal to noise ratio high enough is a real chore with this 1600m{pro} it's much more sensitive than what I'm used to but, no worries. I'll get it going . The city installed one of those LED lights that's just killing me and I may have to shoot even shorter than 10s exposures on many targets.