First Saturn of 2017

June 19th, 2017, 12:45 a.m. local time

It was a hasty session under non-ideal conditions, and I was very tired, but I wanted to try capturing Saturn with my 10″ Dobsonian and DSLR camera.  I have the Jupiter settings down fairly pat, so now it is time to start honing in on taking good pictures of the sixth planet.

A few factors became obvious when I started.  First, since Saturn is much lower towards the horizon, I am going to have to use my counterweights (a bunch of “C” clamps) to keep the Dobsonian from falling over with the camera attached.  For last night, I just held the tube up manually.  I only got about 1,100 shaky frames across back-to-back videos.

Next, it will be a challenge to get the ISO and exposures right, since Saturn is fainter than Jupiter.  With Jupiter, I could achieve focus by setting the camera’s option to overexposure and then focusing in on Jupiter’s moons.  Titan seems too faint for this focusing method to work.

Last, it is going to be a bit uncomfortable over the next month trying to photograph in Summer conditions.  I have come to love the Winter for stargazing – no bugs and you can just layer up.

Forecasted viewing is pretty bad for the rest of the week.  The only good news is that Saturn is still appearing a bit too late in the evening, as I must wait until after midnight to view it due to the tall Southeast obstructions in my way.  Hoefully things will look up in a few weeks.

Hunting the International Space Station

ISS on June 7th, 2017

During this past week I made an effort to track and photograph the International Space Station.  First, on the night of June 5th, I waited for it with my binoculars at the scheduled time for my location.  It did appear in my sky at the appointed time, going from NNW to E.  It was bright and of course moved quickly.  The binoculars did not reveal any additional details that I could not already see with my eyes alone (in other words, nothing).

Now trusting the Interweb’s timekeeping for the ISS and having a general idea of where to look for it relative to coordinates, two nights later I set up my camera on tripod to take what pictures I could.  Because the ISS is so fast, I had to leave my alt-azimuth tripod knobs loose.  This was not too big a deal, as I was able to typically get three to four pictures with my IR remote before the station moved out of view.

In reading NASA’s recommended camera setup for photographing the ISS, I immediately knew my long 300mm lens was about half their suggestion.  They essentially say you need a nice long telegraphic lens.  Still, I was undeterred.  Of the images I took in those brief three minutes, the above I consider the best.  This is a highly magnified section of the original, taken at f/8, 1/1000 seconds, and ISO 3200.

On Sunday night yesterday, I attempted more pictures during the ISS’s even longer four-minute flyby.  But all of these were either blurry or at a bad angle, as all I got were blobs.

To see something really interesting about the ISS, I recommend checking out Jim R’s cool capture of the ISS transiting the Sun.

A Bird, a Plane, a UFO?

Click for full scale.

June 6th, 2017, 8:04 p.m. local time

I caught a bunch of interesting shots of the Moon tonight, along with a few other objects in the sky.  See the tweet below for a good capture of a plane below the Moon.

A short while after the “good” plane, I caught something else, this time much higher.  In the image above you can see a spec in quadrant 1.  Now usually I am shrinking/compressing images for the blog, but this time I am blowing one up.  Here is an expanded view of that dot:

This is likely a plane’s fuselage.  But it just seemed awfully high in the sky for a commercial plane.  What do you think it is?  Satellite?  Aliens?

Constellations II: Leo the Lion

Click to enlarge and discover many stars!

Five weeks.  That is how long I had to wait from my first session photographing Leo the Lion to my second.  That is how long I had to wait for a mostly clear night, but even then, in the early evening of May 29th, I just finished my shots in time before large clouds rumbled in.

Five weeks prior, on April 22nd, the skies were much clearer and Leo was still directly overhead.  But as that was more of a test-shoot, compiling light, dark, and bias frames with my Canon EOS DSLR camera, I wanted to get a second set to see if there was any noticeable difference in the final imagining.  In particular, I wanted to shorten the focal length from f/22 to f/14, about mid-range.

I don’t think the focal setting change made much of a difference, but at least I did learn a few more things about the stacking software, DeepSkyStacker.  For example, the stacking “Intersection Mode” works wonders if you have to move the camera a bit and to ignore the stray wisps of clouds.  I know now for future reference that the sky does not have to be perfectly clear, just clear enough.  I can also take as many light/picture frames as I want, so long as I keep the object approximately centered.  DSS figures out the rest!

The one aspect of this technique I wish I could improve is to highlight better the apparent magnitudes.  Regulus is the brightest stars in my picture, but you cannot tell.  I don’t want to faux edit the image just to make the brighter magnitude stars bigger, but I do want to research possible PSP techniques to highlight the bigger stars.

I am also amazed at how accurate the picture is.  Compare the above image with this star chart and you can mentally plot the smaller stars.  Pretty cool!

Moon, May 29th

Shot with Canon EOS Rebel SL1, f5.6, ISO 200, 1/200 sec, 300mm focal length.

May 29th, 2017, 9:40 p.m. local time

Keeping notes on your past work is a good thing.  When I saw the Moon above, I knew it would make a good picture through my DSLR.  But then I thought, “which camera settings are needed tonight?”  Fortunately I keep a log from my past images, so I know at least approximately what the settings should be.

Using the manual settings from prior shots in April of a much fuller Moon, I knew what to try for this crescent Moon.  My only concern was that since these settings were for a fuller/brighter Moon that I would have to increase the exposure.  But I think it turned out fine, reaffirming my camera’s “Moon settings” with its longer lens.

And here is a tip for checking camera settings on an image.  Most newer cameras should store these settings as part of the image file’s metadata.  I don’t know about Mac OS, but in Windows if you right-click on the image, choose Properties, and click the Details tab, you should see the camera’s settings somewhere there from when you took the picture.  Note that this might not work for videos, only still pictures, but may vary by camera.

Moon, Pollux, and Castor, May 28th

From left to right: Moon, Pollux, Castor

May 28th, 2017, 9:30 p.m. local time

The Memorial Day weekend provided a few good nights of clear or mostly clear skies.  On Sunday the crescent Moon was low in the West, complete with Earthshine.  Though my smartphone does not do justice to the shape or contrast you would have seen live, you still get the idea from the picture above.

The Moon was in proximity to the constellation Gemini.  In the same frame you can see its two brightest stars, Pollux and Castor, which are the heads of the twins within the constellation.  It is difficult to see the rest of Gemini in late May since it is near the horizon and hidden by light pollution.  But in the Winter, when Gemini is high overhead, it is possible to ascertain the general shape.

Daylight Moon with Venus

May 22nd, 2017, 9:20 p.m. local time

Normally I complain about my blocked view of the East sky, due to all my trees and neighbors’ houses in the way.  But sometimes the setup has its benefits.  Today this barrier sufficiently shielded the Sun so that I could find the late stage Waning Moon.

And I thought I was only shooting the Moon, but after reviewing the wider images I noticed that Venus was also picked up!  It may be hard to see, but look above and to the right of the Moon.  The planet was not visible to the eye alone, but was still available with the right camera exposure.

Here is a different, closer view, focused on the Moon:

This last picture, a wide view, approximates what this Moon phase actually looks like when the Sun is out:

Looking ahead, the weather forecast is miserable through the Memorial Day weekend.  Rain and clouds.  This morning it is very bright with no clouds, but as always seems the case, thunderstorms are predicted an hour after sunset.

Summary of My Stargazing Nights Most of This Week

dark-clouds-02

Telescope goes out
Sudden clouds herald more rain
Telescope comes in

 

Short Animation of Io, Jupiter, and Europa, May 16th

On the night of May 16th, despite high winds I attempted to put together a sequence of Jupiter images to make an animation.  I took video approximately every 20 minutes for six capture sessions in total.

The above animation is only showing two of those six final images.  Problems with the others were different light intensities and increasing cloud cover.  For reference, here are the first five images so you an see what they look like.  The above animated GIF was taken from the second and third images.  The sixth image is not shown because it was simply garbage due to the clouds by that time.

Session #1

The sky was by far the clearest during the first capture session.

Session #2

Session #3

Session #4

Oh look above, there is Ganymede!  It just popped out from behind Jupiter!

Session #5

You can see the quality of this final image is noticeably degraded from the prior four, due to the encroaching clouds, which made the sixth session unusable.  Also observe that Ganymede moved a little to the left across the 20 minutes from the fourth image.

(And in case you are wondering, at this time Callisto was way to the right of Jupiter.)