Cloudless skies last night. Supernova shining bright. A delightful sight.
Antha Ann Adkins
Thursday night we had clear skies (though a near-full Moon) and I was able to take another set of M101 and supernova images. Comparing to my previous images, you can see that more time from my driveway gave me more galaxy details, but that they don’t compare to what I can get from darker skies.
Camera geek info:
Canon EOS 60D in manual mode, ISO 800, 1 minute exposures
One of these things is not like the others … I got an image of M101 the Pinwheel Galaxy in February from the lovely dark skies of Dell City, Texas. Since then, light from a supernova in one of its arms has reached us … from 20+ million light years away. And I was able to image that from my driveway! The driveway picture is noisier and dimmer due to light pollution, but you can tell there’s something new there! I’m looking forward to going back out to the dark skies and imaging it again.
Interestingly, the total imaging times of 66×3=198 minutes on 2/16 and 218 minutes on 5/25 are pretty similar, but due to the light pollution, the 5/25 image has less detail, is noisier, and is grainier. On the other hand, the tracking wasn’t as good on 2/16, emphasized by the longer image times, so the stars aren’t circles and the image isn’t as sharp as I would like.
We haven’t had good telescope weather for a while, so I’ve been working on learning more processing techniques. This is my latest effort: M106, a spiral galaxy containing a supermassive black hole in the center. It’s got some nearby friends. How many galaxies can you find?
This is the image where I learned that it’s better to fix the physical alignment of the tracking mount rather than take shorter images to reduce the star trailing – the same amount of time in 30 second images vs 1 minute images takes, well, twice as long to process.
I’m still working on learning the PixInsight processing software, and I have discovered through the Adam Block videos the Generalized Hyperbolic Stretch process, and now I want to go re-process all the galaxies I’ve been working on.
Imaging galaxies and nebulae from my Bortle 8 skies takes hours of data collection and then more hours of computer crunching. I have learned that it’s better to fix the physical alignment of the tracking mount rather than take shorter images to reduce the star trailing – the same amount of time in 30 second images vs 1 minutes takes, well, twice as long to process.
Globular clusters, though, don’t need as much data. So I don’t need to image as long and the processing is faster.
This is M4 and NGC6144, both globular clusters in our Milky Way. Globular clusters contain hundreds of thousands to millions of stars that are gravitationally bound together. What would it be like to live in one? What would the sky look like?
In M4 you can see a “bar” of stars across the middle. This is apparently a characteristic feature.
I have imaged M4 before, but with simpler equipment, and without using stacking and other image processing techniques. I think this version is a vast improvement.
Camera geek info:
Canon EOS 60D in manual mode, 1 minute exposure, ISO 800, custom white balance 3500K
Williams Optics Zenith Star 73 III APO telescope
Williams Optics Flat 73A
SkyTech 2” LPRO-MAX CCD Filter
iOptron CEM40
Friendswood, Texas Bortle 7-8 suburban skies
Processing geek info:
PixInsight
122 1 minute lights
38 1 minute darks
31 0.2 second flats
30 0.2 second flat darks
In our rare cloud-free skies this weekend, I also imaged M13, the Hercules Cluster.
Camera geek info:
Canon EOS 60D in manual mode, 1 minute exposure, ISO 800, custom white balance 3500K
NGC 2359, also called Thor’s Helmet, is an emission nebula that is 15,000 light years away. It is a bubble of ionized gas around a hot central star, Wolf-Rayet WR7. It is 16 x 8 arc min in size, and I was pleasantly surprised that I could capture it with my small telescope. These pictures were made by stacking 64 3 minute images (and cropping).
I’ve been learning PixInsight, and I had some fun with playing with CurvesTransformation on this one. So, in addition to a standard view of the nebula, I created one I call “Thor in a Snowstorm”.
Which do you like better?
Camera geek info:
Canon EOS 60D in manual mode, 179 second exposure, ISO 2000, custom white balance 3500K
Last weekend I did magic with my camera. In a single one minute image, I could only see stars. No signs of nebulosity at all, even zoomed in and brightened on my laptop. But when I stacked 334 images together (5 hours and 34 minutes, taken over two nights), viola! IC434 the Horsehead Nebula and NGC2024 the Flame Nebula were both visible. How cool is that?
Camera geek info:
Canon EOS 60D in manual mode, 60 second exposure, ISO 400, custom white balance 3500K
Williams Optics Zenith Star 73 III APO telescope
Williams Optics Flat 73A
iOptron CEM40
Friendswood, Texas Bortle 7-8 suburban skies
Processing geek info:
PixInsight
344 1 minute lights
28 1 minute darks day 1, 26 1 minute darks day 2
21 0.5 sec flat darks day 1, 20 0.2 sec flat darks day 2
There’s a new comet in the morning skies that hasn’t been in the inner solar system for 50K years and may not return. I got up at 4 AM on Saturday morning to try to catch it. You know I love this hobby since I got up early in the cold! It was an obvious fuzzball in a single 1 minute telescope image, but I couldn’t spot it with image stabilized binoculars. I’m hoping for more clear days as it gets closer and brighter! Have you tried to spot it?
I spent about 8 hours learning how to process comets in PixInsight and trying to get rid of the residual star trails. I’m happy with this image, but look forward to learning some more tricks to improve it!
Camera geek info:
Canon EOS 60D in manual mode, 60 second exposure, ISO 800, custom white balance 3500K
I spent my Christmas holiday working on learning how to use the astrophotography processing tool PixInsight. There’s an enormous amount to learn, and I’m looking forward to learning more. But I am happy with the results of my first project – the Andromeda Galaxy.
For comparison, here is a single 3 minute shot with only basic processing. I think the processing is worth it!
Camera geek info:
Canon EOS 60D in manual mode, 179 second exposure, ISO 1600, custom white balance 3500K
Williams Optics Zenith Star 73 III APO telescope
Williams Optics Flat 73A
iOptron CEM40
Dell City, Texas Bortle 2-3 dark skies
Processing geek info:
PixInsight
18 3 minute lights
10 3 minute darks
50 bias frames
No flats
ImageIntegration Darks to make Master Dark
ImageIntegration and Superbias flats to make Master Flat
After my previous 3 minute Andromeda Galaxy comparison, I decided I needed to get a light pollution filter to get better pictures from my driveway given our Bortle 7 skies. I picked up a SkyTech 2” LPRO-MAX CCD Filter and the image above is the result.
For comparison, here is a picture using the same settings and location with no filter.
And here is a picture using the same settings from Bortle 2 skies.
All these pictures used the same equipment and settings. For the purposes of this comparison, I did not do any processing. I think the filter was worth it. Dark skies are definitely worth it!
Camera geek info:
Canon EOS 60D in manual mode, 179 second exposure, ISO 1600, custom white balance 3500K
Williams Optics Zenith Star 73 III APO telescope
Williams Optics Flat 73A
iOptron CEM40
I also experimented with settings to use from my driveway. Results are in the table below. Lowering the exposure length and ISO cut down on the sky noise. I’ll have to see what I can do with the 1 minute ISO 400 images in PixInsight.
Site
Bortle
Filter
Exposure Length
ISO
Result
Dell City, Texas
2 – 3
None
3 minutes
1600
Gorgeous detail in M31, M32 and M110 visible
Friendswood, Texas
7
None
3 minutes
1600
Almost all white picture
Friendswood, Texas
7
Light Pollution
3 minutes
1600
Bright blue background, M31 as a fuzzball, M110 visible, M32 not obvious
Friendswood, Texas
7
Light Pollution
2 minutes
1600
Teal blue background, M31 as a fuzzball, M110 visible, M32 not obvious
Friendswood, Texas
7
Light Pollution
1 minutes
1600
Dark blue background, M31 as a fuzzball, M110 visible, M32 not obvious
Friendswood, Texas
7
Light Pollution
1 minutes
400
Very dark blue background, M31 as a smaller fuzzball, M110 visible, M32 not obvious
Happy New Year! We always watch time travel movies on New Year’s Eve. This year’s choices: Doctor Who: Destiny of the Daleks (no time travel) and Doctor Who: City of Death (time travel integral to the story).
Space&Aliens 