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Images: Moon, Venus, Antares, M31 Spiral Arms

Posted: 9 October 2013

Monday, 7 October, was cloudy. No observing. The observatory was opened on Tuesday, 8 October 2013, at 1809 MST, 82°F. The sun had set and the sky was clear. At 1815 MST, using 83X, viewed Mercury, then Saturn, then Venus, and finally the moon. I next updated the ISS TLE in the AutoStar for the night's high pass. At 1830 MST, took this D7000 DSLR photo, f/4.5, 1/10sec, ISO 1600, 70mm, handheld:


Mouse over the image or tap on it (if using a touchscreen) to see labels.

I then began preparing to record the ISS pass. Mounted the D7000 DSLR on the 8" telescope at prime focus + 2X Barlow Lens. Used the star Arcturus as a focus test with the Bahtinov Mask. Locked the telescope focus. Made a slight adjustment in the finderscope alignment. All was now ready for the pass, or so I thought.

While waiting for the ISS pass to start, I took this iPhone 5s photo of the western sky. Even the star Antares is visible in the photo.


Just prior to the start of the ISS pass, I noticed that the camera had shifted position. Don't know how that happened as I thought all the screws on the adapters were tight. Unfortunately, there was not enough time left to correct the position so I had to go with it as it was. I did a HD video recording at 1/1000sec, ISO 4000. Tracking was reasonable but the focus was slightly off (due to the camera shift) and the images were underexposed. Image movement also blurred out the station somewhat. Will return to using 1/2000sec, ISO 5000, on my next attempt.

I unmounted the camera and viewed the moon at 83X. I took this iPhone 5s photo afocally and handheld:


Earthshine was nicely captured, but so was some dust on the eyepiece.

Beginning at 1922 MST, I began preparing the D7000 DSLR for prime focus imaging of M31. I added the focal reducer to the telescope and took a final look at the moon. Nice view using the reduced magnification. I then slewed to M31 (the Andromeda Galaxy). M31 and its companion galaxies M32 and M110 were all the same field-of-view (FOV). I could also see M31's spiral arms quite a distance from the galaxy nucleus. At 2000 MST, slewed to Alpha Andromeda for a focus test image.

I then returned to M31, slewed the nucleus to the corner of the camera's FOV, and then searched for a guide star. I located a faint one and did a framing test exposure. I didn't like the framing so I reframed the galaxy in the camera viewfinder. This time I located a much better guide star and did another framing test exposure. I then did a guided 5 minute, ISO 6400, exposure of the spiral arms. Next, I repositioned the galaxy nucleus to the opposite corner of the camera's viewfinder and repeated the search for a guide star and framing test exposures. Once satisfied, I did another guided 5 minute, ISO 6400, exposure. These are the results.



Mouse over the images or tap on them (if using a touchscreen) to see labels. Additional objects in M31 can be identified in the photos using the article "Exploring Messier 31" in the November 2013 issue of Sky & Telescope magazine.

Imaging was completed at 2045 MST. I then did some iPhone software beta testing. Once that was completed, I began closing up the observatory for the night.

The observatory was closed at 2111 MST, 65°F.

Comments are welcome; use the Comments section below, or you can Email Me. Thanks.

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