Cassiopeia Observatory

iPhone & D7000 Imaging: Venus, M99 Galaxy, Saturn;
DSO Observing
Posted: 11 May 2012

The sky was overcast Tuesday and Wednesday, with a brief thunderstorm Wednesday afternoon. Observatory was not opened. The sky mostly cleared on Thursday, 10 May 2012, and the observatory was opened at 1805 MST, 91°F. The sky was hazy and there were some clouds in the north. Viewed Venus, 77X, at 1812 MST. Crescent phase looking very nice.

I then did some tests with my new "POD iPad Platform" (PiP). I planned to use it this night as a place to put the Wireless AutoStar II and some other accessories when not in use.

Next, I captured this (cropped) view of Venus using the iPhone 4, 154X, moon filter, Camera app, MX-1 afocal adapter:

At 2002 MST, I viewed Mars, 77X. At 133X and 206X, the very small North Polar Cap, the sunrise cloud, and a dark area were visible. However, seeing was not very good even though Mars was near the zenith. I then viewed Saturn, 77X. Four moons were visible: Titan, Dione, Tethys, and Rhea. I tried for Enceladus at 133X and 206X but it was not seen.

I slewed to M99 (galaxy) at 2018 MST, my DSO imaging target for the night. It was faintly visible at 77X although twilight was not yet over. I began setting up for D7000 DSLR prime focus + Off-Axis Guider imaging. I did a focus test exposure using the star Spica with a Bahtinov Mask. Slewed back to M99 and located a faint but usable guide star. At 2040 MST, I took this (slightly cropped) 5 minute, ISO 6400, guided exposure:

I then checked Observer Pro on my iPhone for possible additional imaging targets. I selected one, but it would not rise until later, and by the time it was high enough for imaging, the rising waning gibbous moon would interfere.

At 2121 MST, I removed the D7000 from the 8" LX200-ACF and did some iPhone imaging of Saturn. This is a (cropped) stack of 738 frames using Keith's Image Stacker and was taken afocally at 154X + moon filter, upscaled 200%:

I then did some more Saturn observing. Four moons were still visible. Cassini Division was very nice at at 206X and 364X.

Beginning at 2215 MST, I did the AutoStar "Tonight's Best" guided tour using 77X. I skipped the planets and stars in the list. I viewed M13, M44, M4, M92, M82, M5, M104, M57, M68, Centaurus A, M51, and Caldwell 53. I also viewed M81. I then checked on the supernova 2012aw in the M95 galaxy; the supernova was still faintly visible. Next, I viewed the lovely double star Albireo, low in the east. I then returned to M13, the Great Globular Cluster in Hercules, for a more detailed look. Using 133X and even 206X, the star cluster was impressive, with many stars visible. I then viewed M92, another globular cluster. It was not quite as impressive a view as M13 at 206X, but at 133X, the view was good, with many stars visible.

At 2304 MST, I slewed to my next imaging target (as IDed by Observer Pro): NGC6302 (Bug Nebula, planetary nebula) and began waiting for it to rise above an obstruction in the southeast. I viewed it at 2320 MST, 77X and 133X. It was too low for a good view, and by the time it rose higher, the rising moon would definitely be interferring. I defered imaging to a future session. I decided to close up for the night.

Closed the observatory at 2347 MST, 65°F. The "POD iPad Platform" performed as expected and is already making a nice addition to my observatory.

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