Winter Star Cluster M46 and Planetary Nebula NGC2438

Hello All, I was out observing last night under superb transparent skies with my C8, when looking at some winter star clusters, I decided to have a go at M46 as it looked absolutely perfect through the scope. Also was the added bonus of a planetary nebula NGC 2438, a magnitude 11, 65" in size shell easily seen to be within the cluster that gave me a great opportunity to get two deep sky objects in the same shot.

Now I don't claim to be great at deep sky imaging and I did'nt expect to get a great result, my set up was just with the C8 and a canon 300D. I have no autoguiding whatsoever, I had to manually focus myself, and with some light pollution, a relatively bright moon, and errors in the RA motor drive easily seen in the shots where stars present themselves as 'doubles', I knew I had a challenge. There was no wind so I set about the task.

I took 30 exposures in all, 18 30second and 12 60 seconds at ISO 1600 - hence the background noise. I had to throw away 21 shots !!, and so I manually stacked 7 30second and 2 60 second exposures. I had to do a little processing in noiseware and photoshop to get this result. I'm actually thrilled to see the planetary nebula against the background of this lovely cluster..

Any tips that I could do to better this shot?? Maybe some of you guys could give it a go? Visually it's on my favourite list now!
I hope you like it as I have...
Keith..

A mag 11 planetary nebula, and you're asking us for assistance! Any chance of some easier images/questions Keith?

My only recommendation I suppose would be to drop down to ISO400 and increase the exposure time. I did some trial photos previously as high ISO settings and didn't find those settings of any use. Personally, ISO400 is as high as I would go. Any higher, the level of noise you get far exceeds any other benefits - at least that's been my experience anyway.

Hi Michael, I found that with my set up, I really can't go past a 60second exposure, there's just too may trails/doubles from the small errors in the motor drive

Still - I will try to go easy on ya next time :twisted:

Keith..

Keith,
Thats a grand image, nicely done, I just love the planetary nebula image there.
The star points are a little stark, maybe use a little gausian blur to soften them up, mask out the nebula so you dont loose that.
Thats another one on my target hit list :lol:
You're not alone on the number of images lost, on a bad night you can easily loose over 3/4 of your images, imagine doing this with film photography!!

Hello All, I was out observing last night under superb transparent skies with my C8, when looking at some winter star clusters, I decided to have a go at M46 as it looked absolutely perfect through the scope. Also was the added bonus of a planetary nebula NGC 2438, a magnitude 11, 65" in size shell easily seen to be within the cluster that gave me a great opportunity to get two deep sky objects in the same shot.

Nice one Keith! Good to get this double DSO visually and photographically.

You have done it again keith....i just love that image!!