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The North America Nebula

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  • September 5, 2019
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I’m still new to astrophotography, so I’m trying something new with every session. This time I had new telescope upgrades to try out. I added a Pegasus Astro FocusCube 2 for automatic focusing and bought a Pegasus Astro FlatMaster to create flats. I also purchased a 32-foot USB 3 extension cable to control the rig from inside the house. I got tired of all the mosquitoes trying to eat me.

Telescope Upgrades

I had initially picked two targets for this session, the North America Nebula and the Heart Nebula. The clouds had different plans, so I was only able to capture the North America Nebula. I did take a bonus shot of Deneb, but I had the settings wrong. The resulting image was useless.

Auto guiding has been an issue in my last couple of sessions. I had not been able to get PHD2 to talk to my CGEM II mount via CPWI. I ended up having to rely on the mounts tracking functionality and could not take exposures longer than two minutes. I traced the issue to CPWI and am happy to say that the problem was resolved by upgrading CPWI to version 2.2.3.

The FocusCube 2 was an awesome addition. I was able to obtain a good focus faster using a Bhatinov mask and the focus assistant in SharpCap. I can control the focus from my computer via ASCOM or the FocusCube 2 application. I don’t have to go outside and manually turn the dial. There is also an autofocus feature in SharpCap that I have not played with yet. To take full advantage of the FocusCube 2, I will need to configure the capture software to control the focus throughout the night. I have not figured out how to do that in SharpCap. I might need to move to another tool, such as Sequence Generator Pro.

Once I finished the polar alignment and obtained a good focus, I pointed the telescope at the North America Nebula and forced the calibration routine in PHD2. I was not getting the horrible sine wave in the graph, and I did not see elongated stars in three-minute exposure images anymore. I set SharpCap to take 20 three-minute exposures. I was already inside the house thanks to the 32-foot USB extension cable, so I left my laptop on the kitchen table and went to my office to research my next target.

32-foot USB 3 Extension Cable

After an hour, I checked on SharpCap to make sure the images were captured. I then covered the telescope and used SharpCap to take dark frames. The new thing I wanted to try was to capture flats. I bought the Pegasus Astro FlatMaster to help with that. It is a dimmable LED panel that you place over the telescope lens to evenly illuminate the field of view. Flat frames are used to remove dust, smudges, and vignetting. Unfortunately, I did not capture the flat frames correctly. They were overexposed and ended up being useless. Here is the final image after processing with Astro Pixel Processor:

The North America Nebula

This image came out even better than my Elephant’s Trunk Nebula image. Getting auto-guiding to work made a big difference. There are a couple of issues with the image that I’ll need to figure out. The stars in the corners are elongated, that may be an issue with spacing and the field flattener. I’ll add another spacer to see if that helps in my next session. There is also glare on the top left side. At first, I thought there was stray light hitting the telescope, but I think its light from a bright star, 57 Cygni. That star is just out of the frame. I’ll need to be more careful with framing next time and not leave a bright star close to the edge.

My next target is the East Veil Nebula. I hope to improve the tracking in PHD2 and figure out how to properly capture flat images. I also want to compare two-minute vs. three-minute exposures.

Bonus image of Deneb that did not come out right…

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