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PZT Installed & First Use;
Imaging: Moon, Jupiter Moons, ISS

Posted: 17 April 2016

Clouds moved in mid-afternoon on Thursday, 14 April 2016, with increasing winds, eliminating that night's session in the observatory. Friday, 15 April, was mostly clear but there were strong winds during the daytime and evening, creating dusty/hazy skies.

A local resident gave me several astronomy books and atlases. Nice additions to my already large astronomy library.

photo photo

Saturday, 16 April 2016, dawned clear and calm. A local Antelope Squirrel was enjoying breakfast at one of our new bird feeders:

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The POD Zenith Table (PZT) installation was completed on Saturday:


I will post a detailed report about the PZT in the next day or so.

Open: Saturday, 16 April 2016, 1835 MST
Temperature: 79°F
Session: 948
Conditions: Mostly clear, some clouds in north

This night would be the first use of the POD Zenith Table (PZT). I would also continue testing the repaired Wireless AutoStar II handcontroller. But first I synced the observatory clock to WWV.

1855 MST: sunset. 1901 MST: powered on the 12" LX600, turned off the StarLock. Viewed Mercury at 102X and 271X. Seeing was not good so the view was not very good of the planet, low in the sky. Some clouds had now made their way to the southern sky.

Next, I updated the TLE for the night's short but bright pass of the International Space Station (ISS).

1910 MST: first operational use of the PZT to slide the dome off the POD walls. The PZT is on the north side of the observatory, so this opened up the view high in the southern sky to the zenith.

1915 MST: viewed the waxing gibbous Moon, 102X. Unfortunately, there were now some clouds by the Moon and nearby Jupiter. I did some lunar observing at 271X; some good sights at times. Switched back to 102X for this handheld afocal photo of the Moon using the iPhone 6s Plus:


These handheld iPhone afocal photos were taken using 271X and highlight some nice craters:

Crater Plato

Crater Copernicus

Crater Clavius

1935 MST: viewed Jupiter, 102X. The four Galilean Moons were visible, along with a "fake moon". This handheld iPhone photo (cropped), afocal 102X, captured all five "moons":

Mouseover or tap on image
Mouseover or tap on image for labels

Then tried viewing Jupiter at 271X but seeing was not good enough.

Began preparing the D7200 DSLR for prime focus imaging of the ISS. 2000 MST: moved the dome back onto the POD walls since the ISS pass would start and end in the northwest sky. 2012 MST: began setting up for the ISS pass, which would start at 2042 MST. First slewed to the star Capella, which would be used with the Astrozap focus mask for a focus test image with the DSLR. Mounted the DSLR at prime focus + visual back and did the focus test image. Then tweaked the finderscope alignment. 2027 MST: ready for the ISS pass.

With the telescope slewed to the pass start location I could not get my eye to the finderscope eyepiece as it was too high up. This problem will be somewhat alleviated once the pier is installed as it is 2 inches shorter than the tripod. After the ISS pass started I eventually got the ISS into the finderscope but the pass was so short that only a few frames captured the space station before it entered the shadow. This image is a single frame from the HD video, 1.3X, 60 fps, 1/1600sec, ISO 6400, White Balance Auto, and shows the size of the ISS (lower left) in the camera field-of-view at prime focus:


The left image below is from the same frame but cropped. It shows the solar panels, but the station core is overexposed. The right image below is from another frame as the station began entering the shadow.


I still need to refine the exposure setting and optical configuration of the 12" LX600 for ISS imaging.

2050 MST: began closing up. The repaired Wireless AutoStar worked well again on this session.

Close: Saturday, 16 April 2016, 2103 MST
Temperature: 54°F
Session Length: 2h 28m
Conditions: Mostly clear

Now that the PZT is installed I will begin finalizing the pier installation. I will make the final location determination to provide the maximum walking space around the telescope inside the POD and to maximize the amount of zenith access to both the 12" main telescope and the StarLock telescope.

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