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First Time Capturing a Nebula

I have already taken pictures of planets, stars, a couple of galaxies, and a globular cluster. Now it was time to capture a nebula. I picked two targets: the Iris Nebula and the Elephant’s Trunk Nebula.

There was no reason for picking the Iris Nebula other than it looked cool on Stellarium. I chose the Elephant’s Trunk Nebula because my mom loves elephants. I figured this would be a test session since it was my first time trying to capture a nebula.

I had one new addition to my rig. I added a Dew-not heater strap to the guide scope. I did figure out why the dew heater strap did not turn on during my last session when I was capturing Andromeda. The Pegasus Astro Pocket Powerbox needs to connect to a computer via USB, and the control software must be installed. The only other difference in the setup was swapping to the Optolong L-Enhance instead of the L-Pro filter.

PHD2 is still having issues connecting to the CGEM II mount via CPWI. There is an update to CPWI that I need to install that I hope fixes the problem. I did not get a chance to install it before this session so the mount will be guiding on its own again. I was not too concerned since the CGEM II has been doing very well on its own.

Once the telescope was pointing at the Iris Nebula, I set SharpCap to capture 30 2-minute exposures. I went back inside to do some research on capturing darks since I wanted to try that with the next nebula. Here is the resulting image after processing with Astro Pixel Processor:

Iris Nebula

One hour of data was not enough to capture all the details of this nebula. That or I did not process the image correctly. The nebula should be blue, and you should be able to see dust clouds around it. I’m not sure if I need more exposures, darker skies, or better processing. I might need all of that.

I moved on to the Elephant’s Trunk nebula, but first, I used SharpCap to capture dark frames. A dark frame is used to capture the noise created by the cameras sensor and electronics. You take a dark frame by covering your telescope to prevent any light and taking pictures using the same settings and exposure you’d use on your actual target. Once you have a dark frame, you can use it to subtract the noise from the images you capture. An example of a dark frame, I stretched it a bit to show more of the noise created by the camera:

Dark Frame Example

The glowing light on the top right is the amp glow that is produced by the cameras sensor. I’ve mentioned having amp glow in my Andromeda images which I hid when processing the final image. I will now be able to remove the amp glow and all the additional noise using the dark frame.

I only took ten 2-minute exposures of the Elephant’s Trunk nebula because it was getting late. The final image after using the dark frames to remove the amp glow and noise with Astro Pixel Processor:

The Elephant’s Trunk Nebula

I was blown away by this image. I still can’t believe I was able to capture this from my backyard. This image has encouraged me to keep on going with this hobby. I can’t wait to capture more nebulae. My next target will be the North American Nebula.

Bonus image of Vega that I took while doing a one-star alignment.

Vega
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  1. Pingback: The North America Nebula | Ruben's Thoughts

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