Tag Archives: calculation

Sequenced Shots (How To)

How on earth did I end up with this:

Annular Eclipse Sequence [C_040079+fives]

What I started with was lots of shots that looked liked these first three images – i.e not much of anything.

As I went along I ended up combining the “specks” into the image at the lower left. I combined the sequence with a shot taken just after sunset (middle bottom) and the result is as shown in the lower right.

We will soon provide the explanation of how to create the result. First we would like to give some clues about how the shot was planned – because, as it turns out, planning is an important part of all sequences like this one!

Avoidable Technical Content

The May 20, Annular Solar eclipse was well documented. Particularly handy is Nasa’s map based application. Choose a spot on earth by clicking on the map and some useful data pops up:

See those highlighted numbers… they tell you that when the eclipse starts it will be 31.5 degrees high in the sky, and when it ends it will be 5 degrees high – about 27 degrees top to bottom.  Allowing another 5 degrees above and say 10 below we need an image that spans 42 degrees in one direction.  Looking at the Azi numbers  The eclipse begins at 270 degrees (due west) and ends at 292.2 degrees (WNW).  So to take that all in and allow a little breathing room we need about 30 degrees.   Thus we know our field of view needs to be somewhere around 42 degrees vertically and 30 degrees horizontally. Already it sounds like we would prefer portrait mode to keep the sun/moon as large as possible. Using one of the many online tools, like the Angular Field of View Calculator by Tawbaware. Canon people might prefer the “easy to click, but perhaps not so easy to understand Canon equipment specific calculator.”

On a full frame camera, the 50 mm lens comes out to 39 x 27 degrees. which would just fit the whole sequence.  I decided to use my 70mm lens – because I already had a solar filter for it. My plan was to wait until I could catch the sun in the upper left of the frame and the foreground I wanted at the bottom. When the sun arrived, I slapped on the solar filter and started automatic 30 second intervals between exposures.

Or Just Go with Luck

Perhaps my first attempt was not so well planned.

Mamma Glows, Baby Shines

I was too interested in keeping Mt Tamalpais in the picture and ALMOST didn’t get the whole moonset. I know better now! Over three years ago I described how I created the image.  The technique is an extension of my previously described Easy HDR method.

To Be Continued…

In Part 2 of this article, we will show you a few helpful little addenda to make the process easier to manage. We will reveal a Photoshop-only method to approach the problem, AND for good measure a nifty tool to make it easy as pie.

Meanwhile if you are intrigued by the moon, you might want to join us from WHEREVER you are on one of our fun, informative, and oh so reasonably priced Moonatic Webinars.  Or maybe the next Photo Manipulation webinar is just your size.