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Howard Dutton
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I took this shot of the first quarter Moon last night. This is the central region along the terminator. The very technical point cell-phone camera at the eyepiece then shoot and hope for best method was used. This was at 211x magnification and shows a portion of the view through a 3.5mm eyepiece in my 100mm refractor (740mm FL.) The sky was clear and the seeing (atmospheric steadiness) was quite decent. I did a little sharpening in Photoshop but otherwise untouched.
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Taken last Saturday night. Messier 97 (The Owl Nebula) and the Galaxy Messier 108 just fit in this frame. Taken through a 10" f/4 Newtonian 'scope using a Canon 450D DSLR.
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Here's a short video of the Moon/Aldebaran occultation from Saturday night (about 11:05pm Local Time in Western Pennsylvania.) This is a sequence of 5 images taken over 5 minutes.

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Here's my first image of 2017, the Pleiades. This was shot using a Canon 450D on my 10" f/4 Newtonian. It's just a quick stack of ten 120 second images.
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I haven't imaged the Pleiades since, well, it was on film back then. This shows a bit more detail, but no color. My 2" Wratten blue filter doesn't cut it for this object. I took the image with my 10" f/4 Newtonian, G11 (OnStep) mount, and Lumenera LW11059 camera. The full-frame KAI-11002 sensor covers some sky. Too much, in fact, for the coma corrector so this is cropped square. The image is a median stack of 10 x 2 minute frames, flats were applied but no darks, curves in Photoshop. This was shot unguided so tracking isn't amazing, collimation is still off a little too.
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And finally, here's what the tracking of my goto Dobsonian looks like. I turned tracking off about 2/3 of the way through the video for comparison. Not bad for 3D printed plastic gears. I should note it's just coincidence that the star traveled straight up in the frame when tracking was turned off. Both altitude and azimuth axes had to run at the correct rates to hold the star in the center of the frame.  This little camera has 640x480 resolution and gives about 1 arcsec/px. So the field of view is 10' x 8' size and, for example, a 250x Plossl eyepiece would give a similar view.

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Here's a short video of my goto Zhumell Z12 Dobsonian moving around a little before I did some testing on Thursday night.  A minor tracking problem due to a firmware bug needed to be corrected, but the smoothness of tracking looks ok.  Maybe a little rough at very high power, but it was rather windy so hard to tell.  Even so, still obviously way better than no tracking.  I didn't bother leveling the mount so goto accuracy was as expected, useful but not great.  Short gotos after finding a bright star in the area were fine, but further away things would worsen.

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Here's what the OTA and base look like now. The altitude drive on the side panel is mounted on a board which is held on by two thumb screws. Loosen the screws and the worm can be dropped down 1/4" or so. Then put the OTA on the base and raise the alt motor board until the teeth engage and tighten it down. As I said, motor cables still need to be made. I'll design and 3D print some cable clips to make a neat job of running those cables back to the controller too.
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11/30/15
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I messed up the gear part of the new altitude axis two part 3D print. I printed the teeth straight, but they need a 3 deg angle. Since I want to demo the 'scope at this Wednesdays astro club meeting I decided to use the less than perfect first print. So I mounted up the gear, machined the altitude axis worm, made the modifications to the base, and finished the drive. I even did a few test slews and it seems to work well. Next, I need to make cables for the motors so I can try to actually use the goto system and really see what tracking looks like. Pictures soon.
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