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D7000 DSLR Imaging: Planets, Moon,
NGC2419, NGC2997, NGC4631, NGC3201

Posted: 25 February 2012


After my previous long session, the clouds once again returned. Gee, am I detecting a pattern here? A long session in the observatory followed by two cloudy nights. The sky cleared on Friday, 24 February, so I opened the observatory at 1806 MST, 77°F. I first viewed the moon, then Jupiter, at 77X. At 1814 MST, against a bright sky, only three of the Galilean Moons were visible. A minute later, the fourth moon popped into view. At 1816 MST, viewed Venus, then Mercury, 77X and 206X. I then did some sky photography showing Jupiter, Venus, the crescent, and even Mercury, using the iPhone 4 and D7000 DSLR. I tweeted the iPhone photos from the observatory. Here are the D7000 photos. The first photo shows Jupiter (faintly visible at the top near the dome), Venus (just above the left fork arm), and the moon (next to the finderscope):

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This next image shows Jupiter (top), Venus, the crescent moon, and Mercury (very faint, straight down from the moon and just above the tree limb):

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I did some iPhone 4 afocal and D7000 DSLR prime focus imaging of the moon. I tweeted an iPhone photo from the observatory. Here are two of the D7000 DSLR images, the first at prime focus, 1/250sec, ISO 1000, and the second at prime focus + 3X TeleXtender, 2/200sec, ISO 3200:

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I then did some prime focus + 3X TeleXtender imaging of Venus and Jupiter using the D7000 DSLR. This is Venus, 1/1000sec, ISO 500, cropped from the full-frame image:

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On the left below is a single exposure, cropped image of Jupiter, 1/200sec, ISO 2000. On the right is a stack of 753 frames from a 30 second video recording, 1/400sec, ISO ISO 5000, cropped.

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I also did a "hat trick", ISO 1600, exposure of Jupiter to capture the four moons (cropped image):

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I ended imaging at 1943 MST. Viewed Jupiter and then the crescent moon at 206X. Watched a star get occulted by the earthlit side of the moon. Earthshine was pretty at 77X. At 2002 MST, I began using Observer Pro on the iPhone to find some DSOs for observing and imaging. I selected four faint ones: two globular clusters and two galaxies. At 2030 MST, viewed NGC2997, a faint galaxy. It was just barely visible at 77X, low in the southeast sky. Next, was NGC2419, a faint globular cluster, barely visible at 77X. I then viewed NGC4631, a nice edge-on galaxy, 77X, low in the northeast. The fourth selected DSO, NGC3201, a faint globular cluster, had not yet risen.

At 2042 MST, I began setting up to image NGC2419 (globular cluster) at prime focus. Did a focus test on Regulus using the Bahtinov Mask. This is an unguided, 30 second, ISO 6400, slightly cropped image of NGC2419:

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I ended imaging at 2054 MST and took a quick look at Mars, 77X, still low in the east. The North Polar Cap and a dark area were visible. I then returned to NGC2997 (galaxy). It was easier to view now but still too low for imaging. While waiting for it to get higher in the sky I prepped the D7000 DSLR by adding the Off-Axis Guider (OAG). I mounted the camera on the 8" LX200-ACF at 2126 MST, and slewed to Sirius for a focus test with the Bahtinov Mask. Then back to NGC2997 and searched for a guide star. I found a faint one and did a 5 minute exposure. Unfortunately, the star was too faint and my manual guiding was not precise. I selected another star and did another 5 minute, ISO 6400, guided exposure. This is NGC2997, slightly cropped from the full-frame image:

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Next, slewed to NGC4631 (galaxy), did my usual search for a guide star and framing test exposure. This is a guided 5 minute, ISO 6400, exposure, cropped:

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Then I slewed to my last DSO imaging target, NGC3201 (globular cluster) but it was behind a tree. I rechecked the focus using Sirius and began waiting for the cluster to clear the tree. At 2305 MST, I began imaging. This is a 30 second, ISO 6400, unguided and uncropped image:

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I removed the camera from the telescope and observed NGC3201 and NGC4631 at 77X. I then viewed Mars at 206X and 364X. Seeing was not ideal but there were good views at times. I then mounted the D7000 DSLR at prime focus + 3X TeleXtender and did a focus test on Regulus with the Mask. Then went back to Mars and began imaging at 2345 MST. On the left below is a single cropped exposure, 1/200sec, ISO 500, and on the right is a stack of 738 frames from a 30 second video recording, 1/250sec, ISO 500, cropped.

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I plan to continue trying to get better images of Mars as it approaches opposition on 3 March. I ended imaging at 2351 MST, and viewed Mars at 133X. Seeing was still not ideal. I then took a quick look at Saturn through some tree branches, 133X and 77X.

Closed the observatory at 0007 MST, 49°F. Another enjoyable long session.


I have added another astronomy themed Old Time Radio (OTR) radio show on the "Just for Fun!" page on my ETX Site. Have a listen to "Fibber Builds a Telescope".


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Copyright ©2012 Michael L. Weasner / mweasner@me.com
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