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.)

A Montage of Jupiters from the Past Week

My best Jupiter yet?

Astrophotography results depend on many variables.  The stability and visibility of the Earth’s atmosphere.  The telescope used, along with its mount.  The camera.  The focus at the eyepiece.  Exposure, ISO, and other digital camera settings.  Post-processing setup and techniques.  The skill of the astrophotographer.

This past week I was out each night with my telescope thanks to the benefit of clear or at least decent skies for planetary imaging.  It is still Jupiter’s time for 2017 and I am trying to take advantage of every night possible.  My main telescope (10″ homemade Newtonian reflector on a homemade Dobsonian mount) is not an imaging scope.  My camera, a Canon EOS Rebel SL1, is intended mostly for Auto mode pictures at kids’ birthday parties (but it is super light – a prime consideration for balance on my Dob).  With no mount tracking beyond my own steady hand, I can only get about 25 seconds of video before Jupiter moves out of a stationary field of view.

Post-processing is another matter entirely.  It is more art form to properly stack and extract image detail from PIPP, AutoStakkert, RegiStax, and Photoshop.  It is great that these computer tools exist, but the only way to fully appreciate their capabilities is through trial and error.

The above image, taken this past Saturday, may be my best attempt at Jupiter so far.  Of note is that detail, a little, is visible within the Great Red Spot.  Also, this is my first image that left me confident in using AutoStakkert’s Drizzle (enlarging) function.

As I processed my Jupiters this week I posted what I thought were the best of each batch to Twitter.  Here are the several I have not posted about previously on this blog:

This one is neat with Io’s shadow:

Last is a smaller scale version, with slightly different editing, of the image posted at the top:

Merging the Telescope World with the Real World

From left to right: Moon, Callisto, Io, Europa, Jupiter, Ganymede. Click to see the full-sized image.

As mentioned previously, I took several different types of photographs the night of Sunday, May 7th, when the Moon and Jupiter were close.  One of these perspectives was by mounting my digital camera on a tripod to get a wide-field view of the Moon and Jupiter together.  I took many images with different exposures and ISO settings.  Here is one such raw image:

Click to enlarge.

Here, you see an overexposed Moon along with Jupiter.  This shows the distance between the two at 05/07/2017 21:20 Central Time, approximately.

The important aspect of this picture is that it captures all of Jupiter’s Galilean moons.  If you click on the image, you will easily see three of them – Io, Europa, and Ganymede.  Callisto is there, or at least, is there in the raw TIFF image.  You will have to take my word for it that Callisto is there, just very faint.

How do I know which moons are which?  The easy way I follow is to use this Jupiter moon tracker, plugging in times and dates when I take my pictures.  If you enter the time stamp I wrote above, you will get this:

Now while my original source image is nice, I knew I could improve upon it with other images taken that same night at my telescope.  After accentuating Callisto’s brightness a little so we can see it, I used Photoshop Elements to carefully cut out Jupiter and its four moons.  I then overlayed these into a properly-exposed wide-field Moon image.

Next, I wanted to get a good Jupiter into the picture, since the planet itself is overexposed in all my tripod images.  I created the following image from stacked video at my 10″ Dobsonian:

I will shrink this good Jupiter to overlay into the main picture were the bright overexposed Jupiter resides.  But I also wanted to get the planet’s angle right relative to the moons.  So I imported as a temporary layer this other picture I took on Sunday that I previously wrote about:

This “moon” image is the perfect gauge, first to align with the native orientation of Io and Europa in the main image, and then to align the good Jupiter with the moon image Jupiter.  With the proper angle, I then overlayed this good Jupiter on top of the overexposed Jupiter, shrinking it a bit to compensate for the over-brightness of the original.

The final result is the image at the top of this post.

As a final perspective, I used the telescope Moon image I posted earlier and overlayed it in, and then moved the Jupiter system next to the Moon.  This gives you an idea of how wide an area Jupiter and the Galilean moons take up in reference to our Moon:

Click to enlarge.

That’s all for now. I am hoping with the Moon waning over the next week that I will be able to take more constellation pictures, and possibly a few deep sky objects.

Jupiter and Two Moons

Io (left), Europa (middle), Jupiter (right). Taken on May 7th, 2017.

May 7th, 2017, 10:25 p.m. local time

Apparently it is possible to get Jupiter and its moons into the same picture.  You just have to increase the ISO setting.  For the above picture of Io, Europa, and Jupiter, I cranked up my digital camera’s ISO to 1600.  Normally I have it at 400 or 800 for Jupiter.  It leaves Jupiter slightly overexposed, but I think it is a good trade-off given the objective.

In case you are wondering, Callisto and Ganymede were much further out from Jupiter at this time, one on either side.  I have a special treat for later on to show this from another perspective.

Moon Closeup on May 7th

Click to enlarge.

May 7th, 2017, 9:50 p.m. local time

This night produced a bunch of astrophotography goodies: a near Full Moon, Jupiter, Jupiter’s moon, some separate, some together, and at different detail levels.  I will be sorting through all my source images throughout the week.  To start, here is a closeup of the Moon through my 10″ Dobsonian taken with my smartphone, post-processed to bring out additional sharpness and contrast.

I am not sure if it was just the atmosphere or the special brightness of this month (must be that Full Flower Moon) but I was surprised and a little alarmed at how the sky was brightened.  There seemed to be a higher-than-usual glare from this Moon that washed out most stars.  It felt like I was living in the city again.