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New iPad (Retina Display) at the Telescope, D7000 ISS Imaging

Posted: 29 April 2012

Opened the observatory Saturday, 28 April, at 1829 MST, 87°F. There were some high clouds over a lot of the sky. I had two main activities for the night: work with my new Apple iPad (with Retina Display) at the telescope and to make another attempt at imaging the International Space Station (ISS) through the telescope.

At 1839 MST, viewed Venus, 77X, and then the nearly First Quarter moon, 77X. I then took my first photograph with the iPad camera, an afocal 77X, handheld shot of the moon:


The image above is unedited and shows that the iPad can be used to do lunar astrophotography.

I resumed lunar observing, 133X, for a few minutes, and then returned to Venus for a view through some thin clouds at 206X. Seeing was lousy (of course). I attempted imaging Venus with the iPad but the Camera app would overexpose the image. I then updated the ISS TLE for the telescope. At 1927 MST, I tried again to image Venus with the iPad but the dark skybackground would result in serious overexposing of Venus. Went back to moon and captured this (edited) iPad afocal, 77X, image:


These next two iPad photos (edited) were taken at 133X:



A challenge with handheld iPad afocal imaging is holding the large device steady over the eyepiece. Since one hand is being used to hold the iPad (securely) and the other hand is by the shutter button, it is difficult to tap the screen to set the focus and exposure lock at the right place. Handholding the smaller iPhone is much easier.

At 1945 MST, I resumed lunar observing, 206X. There were many nice mountain shadows along the terminator. I then viewed Mars, 77X and 206X. Seeing was still lousy. The North Polar Cap was barely visible. The sunrise cloud was the most obvious thing on the planet (besides the planet appearing orangish).

I began ISS pass preparations at 2006 MST. Mounted the D7000 DSLR at prime focus of the 8" LX200-ACF. Used the moon to focus and Venus to check the finderscope alignment. I did a test video on the moon. At 2015 MST, all was in readiness for the ISS pass, which was to start at 2040 MST. When the pass started, the telescope was pointed a few degrees away from where the ISS appeared above the horizon. I slewed to the ISS and began tracking. Tracking was actually the best I've experienced recently. Unfortunately, the exposure setting I used (1/2000sec, ISO 2500) resulted in the ISS being overexposed. Also, the image scale at 640x424 is small; I will return to HD video recording, 1920x1080, 24fps, for the next attempt. Here is one frame from this night's ISS pass, upscaled 400% and cropped, at least showing the shape of the ISS:


At 2052 MST, I set up to use my new Apple iPad (with the Retina Display) at the telescope. I used Southern Stars SkySafari Pro 3.2 and the Southern Stars SkyWire cable to connect the 8" LX200-ACF to the iPad (just as I have previously done with the iPhone 4). This screen shot shows SkySafari with the connection to the telescope:


It was pure joy to control the telescope using the larger screen. I searched for and selected objects in SkySafari and had it GOTO them. The objects were always near the center of the eyepiece FOV at 77X. And of course, the Retina Display was gorgeous. With SkySafari set to show a small field-of-view, you get a photorealistic view of your selected object:


While I can put the iPad on the the POD Roller Desk, I think I need to come up with something more convenient. Orion Telescopes and Binoculars has a new "Mounting Bracket with Tripod Adapter for iPad/Tablets" that might work if I can't come up with something. In the meantime, I look forward to using the new iPad and SkySafari Pro 3.2 at the telescope for DSO hunting on a moonless night.

At 2121 MST, I took a quick look at Saturn at 77X. Four moons were visible.

Closed the observatory at 2133 MST, 66°F.

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