February 28, 2015 – Dabbling in Astrophotography with the Triple Conjunction and the Moon

Astrophotography from Manhattan?  Are you serious?  Well, at least some AP is possible.  As long as the object is bright.  Really bright.

There was a gorgeous triple conjunction of a brand new crescent moon, a gibbous Venus, and a faraway Mars last week, and I was able to get some snaps through my digital camera.   Here they are above the Manhattan skyline:

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Okay, so you can’t see Mars in that one.  But here’s the three of them in the same field of view through the ST-80 at 17x, with a plane flying through the field:

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Mars is the dim one between Venus and de plane, de plane.

Meanwhile, I’ve been getting a few, more detailed snaps of the moon with my digital camera.  I had been trying to do this with my smartphone, but it’s difficult to line up the camera with the EP, because the camera is somewhere in the middle of the back of the phone, and it’s tough to get the spatial alignment “just right” when you can’t see what you’re aligning.  So instead, I dug out my 8-year-old Panasonic Lumix DMC-TZ5.  It may be old, but it’s still a perfectly good digital camera – 9 Megapixels, 720p video, Leica lenses, lots of exposure adjustments deep down in the menu.  Here are a couple of pics of the moon I took a few days ago with the Mak through the 32mm Plossl, at 48x.

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And here’s another one of the moon, a bit past first quarter, also at 48x through the 32mm Plossl, taken last night:

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I have to say, these came out very well, and I’m kinda proud of them.  But taking pictures at any magnification higher than 48x is very problematic.  These pictures were taken by my just holding the camera right on the eyepiece as steadily as I could.  Having the two touch while I’m holding the camera causes vibrations in the telescope, leading to blurred images.

Not only that, but it’s an ironclad law of optics that as the magnification increases, the light gets spread out over a larger area, the image gets darker, the exposure has to be longer, and that means you have to hold the camera steady for longer – for 1/8 of a second instead of 1/15 or 1/20 of a second.  And that leads to blurred images, too.

More to the point, regardless of the blurriness or not, trying to take pictures at higher magnifications leads to severe vignetting – the cutting off of the full field of view of the eyepiece.  This is noticeable even with my “wide-field” EP, the 32mm Plossl, as it’s a little bit of a job to get the whole moon into the picture.  However, this becomes really annoying when using any magnification that’s higher than that.  Here’s one taken through my 15mm Paradigm, at just 103x:

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No need to adjust your set.  That’s the entire photo.  And yeah, that quality also leaves a lot to be desired.  For whatever reason, even though the 15mm is only roughly double the magnification of the 32mm, and roughly half the field of view, the view through the camera gets severely vignetted.

Moreover, taking pictures of anything else but the moon is extremely problematic.  My attempts to take pictures of Jupiter – even with the 32mm – have been truly pathetic; so, no, I won’t be sharing those attempts here.

There are mounts which you can attach to the eyepiece and to the camera so that everything stays right in the perfect position, and is all nice and steady.  I’m looking into getting one – maybe.  The reason I’m hesitant is because I think it would only be useful to take more moon shots.  Okay, and shots of the sun, too, if I ever get a solar filter.  And while the moon shots are admittedly nice, it seems like an awful waste of money to be able to take pictures of only one thing.

So, it looks like, for now at least, I’ll just keep trying with the point and shoot method.

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