Search for  Astronomy  found 14 posts
Order: Newest / Oldest / A to Z / Z to A
Aug 13, 2013, Tuesday
Meteor Shower    11-16, Juan de Fuca St, Astronomy D300  
Aug 13, 2013, Tuesday
Aug 12, 2014, Tuesday
Moon    Moon, Astronomy 70-300vr  
Aug 12, 2014, Tuesday
Aug 12, 2015, Wednesday
Perseids Redux    11-16, 15/2.8, Astronomy  
Aug 12, 2015, Wednesday
Aug 16, 2015, Sunday
Experimentation    11-16, Astronomy  
Aug 16, 2015, Sunday
Sep 28, 2015, Monday
Blood moon    Moon, Astronomy 70-300vr  
Sep 28, 2015, Monday
Aug 11, 2016, Thursday
Prepping for Perseids    15/2.8, Astronomy  
Aug 11, 2016, Thursday
Aug 13, 2016, Saturday
A Trickle of Perseids    15/2.8, Astronomy  
Aug 13, 2016, Saturday
Sep 16, 2017, Saturday
A mind-blowing trip    Science, Astronomy  
Sep 16, 2017, Saturday
Feb 1, 2018, Thursday
Moon    Moon, Astronomy 70-300vr  
Feb 1, 2018, Thursday
Aug 9, 2018, Thursday
A couple of Perseids    Astronomy Samyang 12  
Aug 9, 2018, Thursday
Aug 13, 2018, Monday
Milky Way    Astronomy Photography, 15/2.8  
Aug 13, 2018, Monday
Dec 21, 2018, Friday
Earthrise    Astronomy  
Dec 21, 2018, Friday
Jan 21, 2019, Monday
Blood moon    Astronomy Moon  
Jan 21, 2019, Monday
Feb 14, 2019, Thursday
Feb 14, 2019, Thursday

Meteor Shower

August 13, 2013   11-16, Juan de Fuca St, Astronomy, D300

To capture a shot of a meteor you need a cloudless, moonless sky, a tripod-mounted camera, a remote shutter release, an exposure long enough to see meteor trails but not so long as to capture star trails, and a glass or two of wine.

This photo was taken during the Perseid meteor shower, which is visible in North America from mid July to mid August. The view is looking south over the Juan de Fuca Strait to the town of Port Angeles, Washington, the bright light source in the distance. Shot with a Nikon D300, 11 mm focal length, f/2.8, 33 sec, and long-exposure noise reduction (LENR). LENR works by following each exposure with a second exposure of the same length but with shutter closed. The second exposure is then subtracted from the first to remove noise. This, of course, doubles the time to take the shot.



August 12, 2014   Moon, Astronomy, 70-300vr

The weekend's clear night skies provided a good view of the moon. Watching the moon zoomed-in in live-view brings home the fact that it's a moving object, so a fast shutter helps. Both were taken on a tripod with a 70-300 vr, spot metering, and both, of course, were heavily cropped in post processing.

The half moon was shot at 220 mm, f/7.1, 1/320 sec; the full moon at 240 mm, f/7.1, and 1/1600 sec.


Perseids Redux

August 12, 2015   11-16, 15/2.8, Astronomy

Meteor shots can be taken with a wide angle lens, a tripod, and a camera set on long exposure, typically 30 seconds or more. A lot of waiting in the dark of course but with some tunes and a glass of wine sitting out under the summer stars is not a bad way to spend some time.

I first tried this two years ago, also in August, during the Perseid shower. Lucky me, on my first night out I got a decent shot of a Perseid meteor. It's the second one below. I used bulb mode on the D300 and a timer on my android along with a wired remote to control the shutter.

So this morning, just after midnight, I spent about an hour taking sky shots to see if I can better the 2013 shot. I used the 15 mm fisheye to get more sky, a little higher ISO as I'm using a newer sensor, and a 30-sec exposure. Each 30-second exposure is followed by 30 seconds of noise reduction so each shot takes a minute, half of which time the shutter is closed and of course that's when I seemed to see the most meteors falling down though maybe I was imagining them. This morning I pulled the 53 shots into Lightroom, jacked up the lightness, and found two with meteors. Not very pretty meteors, though, with jagged trails. I guess I need to keep working on my recipe.

If tonight's clear I'm going to try again, but I'll use a non-fisheye wide angle, the same 11-16 as I used before. I don't like the curved horizon I'm getting from the 15. I'll also use the D800e's interval shooting function which I've been testing.

Perseid meteor      
Perseid meteor over Port Angeles


August 16, 2015   11-16, Astronomy

Sometimes I look at life as a series of experiments. Some experiments are solo (cooking, programming, running), some social (relationship, job, board membership), and they all generate data that I'll use in another experiment.

My current photography experiments are targeting a goal of creating a great shot of a falling meteor. While I'm not there yet I know what i want: many dots of starlight on a blacksky background, a foreground to give context, and all cut with a solid meteor streak. That's all. Well, that's a lot actually, as it depends not only on my skills but also on the weather and the moon light.

Experimentation so far has me using the 11-16 at 16, f/2.8, ISO 1250, and a target of the southern sky. The southern sky is a compromise: Port Angeles puts off a lot of light but any other direction is impeded by trees. I guess next time I'll have to forego the wine and take a drive to a nearby beach. I also wonder if i should boost the iso a bit. More experimentation.

Taking a series of long exposure shots is really tedious so I've found that if 30 seconds is long enough (more than 30 sec requires bulb mode) then Nikon's interval shooting function will take an evenings worth of shots for me, hands free. Interval shooting has three variables: interval length, shots per interval, and total number of intervals. So on the morning of the 14th I decided to take a series of 30-second shots from midnight till about 2 in the am ans so I set up the camera for one shot (aperture, iso, exposure) then set the interval function to take a shot every 65 seconds, with 1 shot per interval, and for a total of 120 intervals. I chose 65 sec intervals because the shutter is open for 30 then closed for 30 (long-exposure noise reduction), which totals 60 sec. I then added 5 sec as a cushion. Once set, all I had to do is press GO then head in for another glass of wine.

This was taken early on the morning of the 14th. I don't like the meteor streak as it's not solid but it sure was easy with the interval shooting function.


Blood moon

September 28, 2015   Moon, Astronomy, 70-300vr

Moon shots taken last night. The first is a cropped shot of the moon in the Earth's penumbra. The second shot is the un-cropped version of the first. The third shows the moon moving out of the penumbra.

Blood moon      
Blood moon      
Blood moon cropped

Prepping for Perseids

August 11, 2016   15/2.8, Astronomy

I spent two hours last night with the Nikon practicing for tonight's Perseid shower. Actually much of the time was spent on the couch, drinking wine, as the camera's interval timer does the grunt work. I didn't expect to catch much in the way of meteors, it was more about getting the exposure right and the interval timer working, so I was pleased to find two of sixty shots show what look like faint meteors. Study the upper left of the shot below and you'll see it, though maybe not on a phone.

Taking a photo of a meteor is different from your typical photo. A wide fast lens is good for this so I used both a 20/2.8 and a 15/2.8. I much prefer the fisheye but I know some people hate the distortion. The camera's settings were as follows:

  • Manual focus
  • Focus lens on infinity
  • 30 second shutter
  • ISO at 1250, maybe more
  • Matrix exposure
  • Long exposure noise reduction (LENR) set to ON (Shooting Menu)

Why these settings? Thirty seconds is long enough to get a nice streak but not so long as to get star trails. The matrix exposure setting is Nikon-speak for whatever is the camera's smartest exposure algorithms. ISO? Well, I'm still experimenting. It's 1250 here. And set LENR to ON so that the camera takes a second shot each time, for the same exposure length, but with the shutter closed. Then the camera subtracts the second from the first, thereby removing some noise. Note this more than doubles the time for a shot as the camera has to perform the calculations and write the image file or files to the card.

Next, place the camera on a tripod and position it to get a broad swath of night sky.

Finally, set up the camera to automatically take a series of photos. The interval timer needs to know how many photos to take and the time between each photo. For example, say you've an hour before you go to bed and so you want the camera to shoot for sixty minutes. A thirty second exposure takes the camera no less than sixty seconds (remember the LENR?) so we can take at most sixty shots per hour. A little less actually. I add a generous 15-second cushion between each shot making the interval 1 min 15 seconds for a 30-second exposure.

Now that we've the interval length and number of intervals go to the Nikon's interval timer. This is a powerful feature but it's a bit awkward to use. Here is the path I use through the timer's menus:

  • Shooting Menu
  • Interval timer shooting
  • Select Now then press right arrow
  • 00 Hr 01 min 15 sec (right arrow moves through)
  • 060 intervals x 1 shot per interval = 0060 shots
  • Select On and press the OK button

While the Nikon was busy I spent some time with the Fuji X-pro2, shooting the sky with the 16mm, and I found it has a similar interval timer, though it can only do one shot per interval.

I am listening to Trouble by Jose James.

Perseid meteor

A Trickle of Perseids

August 13, 2016   15/2.8, Astronomy

A sky-full of shooting stars was what I hoped for but no, just the occasional singleton. A trickle. 48 out of 358 shots had something, which sounds good, but most were but a faint trace. Was I too early? Too late? Wrong ISO? Or was the shower masked by the lights of Port Angeles? Clearly, more experimentation is called for.

The second shot is darker because it was taken later the same evening and has a lower ISO.

I'm listening to the president's 2016 summer spotify playlist: day which triggers feelings of impending loss, the loss of a cool and scandal-free president.

Perseids over Port Angeles      
Perseid over Port Angeles

A mind-blowing trip

September 16, 2017   Science, Astronomy

A brilliant journey through space has come to an end. NASA's Cassini spacecraft spent the past twenty years successfully carrying out its mission to explore Saturn and its moons.

Cassini was launched in 1997 and it took seven years to reach Saturn. Along the way it flew by Venus, Earth, and Jupiter. Upon arrival Cassini took to orbiting Saturn where it sent back stunning photographs of the planet and its moons.

Sad to say, yesterday was Cassini's last day but what a trip it was, and what a testament to the skills of the scientists and engineers at NASA and elsewhere who participated in the endeavor. Whenever I feel despondent about mankind I'll remind myself of accomplishments such as this.

Saturn's moon Titan      
NASA   Saturn and Earth      
Cassini's journey


February 1, 2018   Moon, Astronomy, 70-300vr

Here is a substitute for the recent blue moon which was not visible through the overcast and frequently-raining skies.


A couple of Perseids

August 9, 2018   Astronomy, Samyang 12
The southern sky at 10:41 pm      

My first sky shot with the 12mm on the Fuji. You can see a bit of Milky Way and a Perseid or two. I expect the Nikon with the 15mm will do better --- it's running as we speak, the intervalometer taking a 30" shot every minute or so --- but the Nikon shots will have to wait until morning since it can't zap images to the iPad like the Fuji.

Milky Way

August 13, 2018   Astronomy, Photography, 15/2.8

A slightly better shot of the Milky Way, helped by using a wider lens and higher ISO. Unfortunately, since taking this shot the skies over Vancouver Island have turned grey from smoke and haze.

Milky Way with roof and forest
NASA   Earthrise, Apollo 8, 1968      


December 21, 2018   Astronomy

A small planet, insignificant in size compared to the galaxy, but still our home and one perfectly suited for life, with water and air and soil and a sun nearby to give warmth. John Gardner in The Guardian

Apollo 8, piloted by Frank Borman, James Lovell, and William Anders, was launched fifty years ago today. The mission gave us a new view of planet Earth as well as our first view of the back side of the Moon.
The moon      

Blood moon

January 21, 2019   Astronomy, Moon
The infamous blood moon taken with the Fuji. Looks pretty similar to the Nikon version.

Mars rover Opportunity completes mission

February 14, 2019   Astronomy

A regular day for NASA is a miracle for people like me. Someone on the internet

Something that makes me both happy and sad was Wednesday's NASA announcement that the Mars rover Opportunity spacecraft has ended its mission. Happy because it reminds me humans can do great things. Sad because, well, it's the end of life for the rover.

Opportunity landed on January 24, 2004, fifteen years ago. The rover was designed to last three months but remained working for 14 years. The rover has been quiet since a June dust storm. Opportunity's solar panels could not generate enough power to keep the spacecraft awake.

Opportunity provided an up-close view of Mars that scientists had never seen and it changed the model for planet exploration from studying a single spot to moving about the planet.

Opportunity's success came on the heels of a NASA mission that failed. A mathematical error due to inconsistent use of units, English and metric, caused the Mars Climate Orbiter to disintegrate. This is a story I often shared with my chemistry students as an example of the importance of tracking units.

What an amazing scientific and engineering achievement.

NASA   View from Mars Rover