The Bow Tie Nebula

To finish off this weekend I tried to photograph something I hadn't looked at before.  What I learned about Caldwell 2 is that I'll probably want to barlow it when using the newt, or try capture it with my Maksutov instead.

The nebula was tiny.  Also, since the DSLR has a (relatively) large sensor compared to some dedicated entry-level CCDs, the DSO was even smaller in the result. At first, using the LCD display of the DSLR, I thought my subs weren't capturing anything but some colorful noise in the center of the images.  However, the noise was a little too consistent and large.

C2 (NGC 40) - The Bow Tie Nebula in Cepheus

One thing I've come to appreciate with the CG-5 is how consistently it pinpoints and centers the target in the eyepiece.  Chalk it up to good mechanics and/or a great alignment, but it sure helps the night go more smoothly!

I've really started noticing now how much coma is in some of these images around the edges.  Although I'm able to crop out some of the vignetting and coma, I'm beginning to understand why a field flattener or coma corrector is needed with these faster scopes.  Maybe this is also why people enjoy imaging with catadioptric scopes, too.  The higher focal length helps reduce some of the coma.

The Mak and the CG-5

Since getting the Meade ETX 125, I'd wanted to try take photos of the sky using it.  When I got the C6-NGT, I suddenly had a good mount to try it!

Since the ETX 125 OTA already has a mounting block with dual 1/4-20 holes in it, I just had to find an adapter to marry the scope to the CG-5.  Luckily, ScopeStuff sells just the thing!

Given how much slower the Meade mak (f/15) is to the Celestron newt (f/5), it's not a surprise that the images produced by the mak were much "dimmer".  All things equal, from the camera's perspective (exposure length, ISO), the C6 produced much brighter images.

What I don't recall, and what will necessitate another trip out with the mak, is how much coma was present.

My first shot with the mak and CG-5 was Albireo:

Albireo - Double star in Cygnus

I don't have a good grip on photographing stars yet.

My second shot was a single frame of M57:

Messier 57 - Planetary nebula in Lyra

As an experiment, I decided to do a comparison between a 30 second exposure and a 60 second exposure with all other things being equal:

Messier 57 - Planetary nebula in Lyra

Once I get an autoguider, I'd like to try thing experiment again, bumping up the exposure time incrementally to see how things are affected.

The C6-NGT and Astrophotography Take 2

On this night I decided to try image two targets.  One that I could clearly see with the telescope and another that I couldn't.

This round, two things were different:

1. I spent the time ensuring I had a better alignment.  It took a great deal longer, but the results blew away my first shoddy attempts at taking pictures with this gear.  Instead of doing a simple two-star alignment with an additional calibration star, I did a two-star with several calibration stars AND I performed Celestron's All-Star Polar Alignment routine.
   
   Assuming the All-Star routine really works (which is evidently does), it's really amazing how far off my mount was in pointing to the north celestial pole.  I don't have a polar axis scope, and given other amateur astronomers feedback on the All-Star routine it looks like I may not really need it!
   
   On a good night, the alignment routine will take me 15 minutes.  This is a far cry from the 45min+ needed for a good drift alignment.  I also assume it's not as accurate as a carefully applied drift alignment.  Regardless, the All-Star routine gave me one minute exposures with virtually no trailing.  Maybe I was just lucky!
2. I bought a bahtinov mask from Farpoint Astro.  This took all the guesswork out of focusing and as far as I'm concerned, is a cheap no-brainer accessory to add to your imaging toolkit.  I couldn't imagine focusing without it.  I first tried to make my own, but I eventually decided that $18 bought me a piece of equipment vastly superior to what I could make.

The Easy Target

M92, a globular cluster in Hercules is nice and bright in the eyepiece.  You can easily see it in a short exposure and is therefore easy to locate and center.  You don't have to spend hours imaging and processing to discover that your target is being clipped accidentally.

M92 - Globular cluster in Hercules.  4 x 30"

The alignment is definitely better, with little to no trailing.  However, evidence of coma clearly shows around the edges of the image.  Darn newt.  Well, maybe when I get better at this I can look into a coma corrector.

The Hard Target (for me)

Caldwell 34 -- the Veil Nebula in Cygnus -- is a DSO I can't see from my home with my telescopes, although I have seen it in my 10" newt at a dark(er) site.

I only took one sub of the Western Veil (30 seconds at ISO800) and at first glance I could see nothing...

C34 - Veil Nebula in Cygnus

... but it's there!  This was my first face-to-face with a DSO that would need more subs, a longer exposure and heavier processing to draw out the details.

Here's a Photoshopped version of the same image to help draw out the nebula:

The C6-NGT's First Terrible Pictures

A couple of days after I took my brandy new C6-NGT out for first light, I decided to try hook up my DSLR to it.  The first series of pics weren't great, entirely due to a hasty and beginner's alignment.  The exposures were about 30 seconds each.

My first shot was of M13, a globular cluster in Hercules.

M13 - Globular cluster in Hercules

Compared to my first shot of M13 using the MallinCam, this image's detail is much higher, but trailing is clearly visible from a lousy equatorial alignment.  I was still quite excited about my first shot, though, on a real equatorial platform.

I then decided to slew over to M57 in Lyra.

M57 - Planetary nebula in Lyra

Just like the first shot of M13, field rotation from a bad alignment is obvious; even more so in this picture... I wonder if I bumped the mount after my first imaging of M13.  However, the color from this picture was great.

Overall, I was quite satisfied and excited about my first outing with a more capable beginners imaging set up!