With summer coming to a close, I had one last chance for some deep sky astrophotography under dark skies. Choosing an astrophotography target at a dark sky site requires some serious thought. The key is to focus on an object that will benefit from broadband color data without the need for harsh light pollution filters.
After much deliberation, I decided to spend this rare occasion with my sights set on the Andromeda Galaxy. Cataloged as Messier 31, Andromeda is a massive spiral galaxy that demands attention. This month, it’s well placed in the night sky for your next astrophotography project.
The good news is, the Andromeda Galaxy can be appreciated using nothing more than a stock DSLR camera, a telescope, and a tracking mount. Having the ideal field of view is the tricky part.
The Andromeda Galaxy is primed for imaging this month
Whether you are new to this hobby or have been capturing the night sky for years, I hope that you were able to get out and enjoy astrophotography this season.
Despite the almost record setting rainfall in my area this summer, the season included its fair share of clear nights as well. The warm nights create challenges for DSLR astrophotographers, making thermal noise a real pain. Needless to say, I welcome the cooler nights of September and October with open arms.
Camping Under Dark Skies
Way back in April, I booked a camping trip one of my favorite dark sky sites in Ontario, Rock Point Provincial Park. I was overjoyed to find out that the Saturday night of the trip had clear skies in the forecast. I’ve lucked out with my astronomy camping trips this year, both to Long Point PP and Cherry Springs.
My campsite had all the elements of a great astrophotography site. I scouted out the campsites at the park on a previous visit, to find a site with large open areas of the sky. Campsite 140 included a power supply station, wide open views in all directions and privacy from surrounding campsites.
As always, Rudy provided great company as he is quite used to hanging around me as I fiddle with telescopes and cameras. He even performed his usual backyard ritual of cozying up on the rug I place underneath my deep sky astrophotography equipment.
He was a big hit with the other campers, as many people approached him to say hello. Rock Point has an incredible beach, and Rudy enjoyed some long walks along the shoreline during the day.
William Optics Zenithstar 61 APO
I am delighted to announce that a brand new William Optics Zenithstar 61 APO arrived in the mail on Friday. I have always been a fan of William Optics equipment, having previously used the 72 Megrez doublet, and the WO Field Flat III 0.8X Flattener/Reducer for many years.
With the Z61 arriving on Friday, it gave me one night to get things in order for a dry run, and then an opportunity to test the optics under some dark skies the following night. I am just starting to get my feet wet using the new Z61, so I’ll save my review for a little later. However, my early experiences say a lot about the ease of use and build quality of this refractor from William Optics.
The package included a William Optics Flat 61 Field Flattener, complete with a Canon DSLR T-Mount adapter. The first challenge I faced was learning that the flattener actually threads directly into the 2″ focuser draw tube, as opposed to clamping the barrel into a compression ring.
The build quality and attention to details in the Z61 are evident in the Z61
The camera locks into place securely, ready for fine focusing on a bright star using the buttery smooth dual speed focuser. The temperature gauge is a nice touch and can indicate a need for an adjustment later as the temperature drops throughout the night.
I have stated many times how much I love apochromatic refractors. The forgiving wide fields of view, sharp stars, color correction, and reliability are among my favorite features. The Z61 happens to be a doublet with a focal ratio of F/5.9. This affordable imaging refractor has proven to be a real performer.
- Aperture: 61mm
- Focal Ratio: F/5.9
- Focal Length: 360mm
- Design: Air-Spaced Doublet
- Extremely Portable & Lightweight
- 1:10 Dual Speed Micro Focuser
- Synthetic Flourite (FPL-53) Glass
- Optional Anodized 200mm Dovetail
iOptron SkyGuider Pro Mount
Next up was mounting the Doublet for deep sky imaging on a tracking mount. The Sky-Watcher HEQ5 Pro that carries my Explore Scientific ED102 seemed overkill. If only I had something a little more portable and lightweight? Oh right, the iOptron SkyGuider Pro (On loan from Ontario Telescope and Accessories)
The iOptron mount can handle the Z61 telescope with ease, utilizing the included counter weight for balance. The Zenithstar weighs a mere 3 lbs, meaning the SkyGuider Pro is well suited for this instrument. Perhaps I could have even got away without the counterweight.
The image of the Andromeda Galaxy below is proof that you do not need a bulky motorized equatorial mount for deep sky astrophotography. The iOptron SkyGuider Pro continues to impress me with its reliability and performance.
Deep Sky Astrophotography with a DSLR
Photographing the Andromeda Galaxy
As dusk set in, I did my best to capture the emotions and anticipation felt on nights like this. For a full recap of the trip including my final image, have a look at the video:
The deep sky target I chose on this magical night was the massive Andromeda Galaxy. The focal length of the Z61 (360mm) was a great fit for this object. The skies were so dark, I was able to use the viewfinder in my Canon T3i to locate and frame M31.
I have photographed the Andromeda Galaxy in the past using a larger refractor (Explore Scientific ED80) with more exposure time, on a Celestron CG-5 Mount. The difference in detail is evident, but I believe the Z61 + SkyGuider Pro could produce an image just as deep with enough time.
It’s also worth noting that the color balance changed quite significantly from the original image using a stock Canon DSLR.
In the coming weeks, I will share a detailed review on the William Optics Zenithstar 61, complete with multiple example images. I’ll need to spend some more time with this telescope before giving it an honest review.
The Andromeda Galaxy
The imaging sequence was automated using an inexpensive remote shutter release cable, and fired away at M31, capturing 70 x 2-minute exposures in total. I then shot 40 dark frames and subtracted them in DeepSkyStacker to reduce noise.
The Andromeda Galaxy (Cataloged Messier 31), is a spiral galaxy located about 2.5 million light-years from Earth. It resides in the constellation of the same name and is the largest galaxy in the Local Group. Other notable galaxies in the Local Group include our own Milky Way Galaxy and the Triangulum Galaxy.
The apparent magnitude of the Andromeda Galaxy is 3.4. This makes it one of the brightest Messier Objects in the night sky and can be easily spotted in binoculars or a small telescope.
Imaging Telescope: William Optics Zenithstar 61 APO
Camera Adapter/Flattener: William Optics Flat 61 Flattener and T-Mount
DSLR Camera: Canon Rebel T3i/600D (Full Spectrum Mod)
Filter: IDAS LPS Filter (Clip-In)
Mount: iOptron SkyGuider Pro Mount
Camera Control: Polaroid Remote Shutter Release Cable
Total Exposure: 2 Hours, 18 Minutes
70 x 120s @ ISO 1600
Stacked in DeepSkyStacker with 40 Dark Frames
Image Processing in Adobe Photoshop
Image Processing Workflow:
1. Levels Adjustment
2. Curves Adjustment
3. Set Black Point
4. Increase Contrast (Carboni’s Tools)
5. Increase Star Color (Carboni’s Tools)
6. Star Reduction (Carboni’s Tools)
7. Increase Saturation (Select Color Range)
8. Noise Reduction
9. Smart Sharpen
10. Selective Sharpening
I want to thank everyone for the thoughtful comments on my video, both on YouTube and Facebook. I am very lucky to be able to share my astrophotography journey with you all. You can stay up to date by subscribing to the AstroBackyard Newsletter.