Solstice To Solstice

On Tuesday, December 22, 2015, I strapped another pinhole camera to my back porch to capture another photo of the change in solar elevation over a period of time. This time around, I wanted to capture the sun as it went from it’s lowest point in the sky to it’s highest point in the sky.

That meant I needed to start the capture on the winter solstice (12/22/2015), and end it on the summer solstice (06/20/2016). So, that’s what I did.

Below is the outcome of the 6 month exposure.

You will notice something that appears to be scratches towards the bottom of the frame. At first, I was confused as to how those got there. Then, I realized those “scratches” are actually the silhouette of the cars that were parked on the street and stayed in the same spot for an extended period of time.

As the summer solstice grew closer, and the sun climbed higher into the sky, I knew there was a flaw with the pinhole camera. The pinhole needed to be higher up on the can. Because it wasn’t as high up on the can as possible, the last few months were cut off at the top of the frame.

Luckily, I knew that was going to be the case, so I prepped a new can with the pinhole as high as possible to capture the solar elevation change from the summer solstice to the winter solstice. Now, I get to wait until Tuesday, December 21, 2016 to see the outcome of that exposure!

2,592,000 Seconds Later

UPDATE: Someone informed me that the use of “solar elevation angle” should really be “solar altitude angle”. After researching, “solar elevation angle” and “solar altitude angle” can be used interchangeably. I apologize to anyone that may have been confused.

30 days ago, I made a post about the pin-hole camera I built as part of my first “solargraphy” photo attempt.

As stated in that post, the exposure started on Sunday, February 15th, 2015 at 9:42 AM Eastern.

Today, Tuesday, March 17th, 2015 at 10:42 AM Eastern, the exposure was stopped.

The shutter was open for exactly 2,592,000 seconds.

On March 3rd, 2015, Metro Detroit was hit with a snow/sleet/rain storm dumping 3 inches of snow in the morning, followed by sleet/rain in the afternoon. One of the big things I was worried about was what would happen if the can got wet.

Well, it got wet from the freezing rain, which resulted in the can getting covered in a sheet of ice!

frozencan

I ended up placing my thumb over the pinhole for a couple seconds which started to melt the ice around the area and expose the hole. I wasn’t sure if water entered the can through the pinhole, but there was no way to find out until I cut the can open to retrieve the photo paper to scan it. From what I could tell, no water appeared to have entered through the pinhole.

This specific solargraphy photo captured 10.87 degrees of solar elevation angle change over the 30 day period.

When the sun was at it’s highest point in the sky on February 15th, 2015, the solar elevation angle was 34.71 degrees.

When the sun was at it’s highest point in the sky on March 16th, 2015, the solar elevation angle was 45.58 degrees.

Because the exposure ended at 10:42 AM Eastern on March 17th, 2015, the change in solar elevation angle needed to be calculated up to the last day that the sun was able to reach it’s highest point in the sky, which was the day before on March 16th, 2015.

The solar elevation angle calculations above are taken from the latitude and longitude coordinates of where the pin-hole camera was placed in my back yard.

For clarification, the solar elevation angle is the angle between the horizon and the center of the sun.

Imagine a gigantic protractor (hopefully you know what a protractor is) being placed on the ground and a string extending down from the sun to the middle point of the protractor. That is a “real life” example of how you would measure the solar elevation angle. I used an online solar elevation calculator though since there really is no way to use a protractor.

Below is the result of the 2,592,000 second exposure.

2592000 Seconds Later

You can faintly see the house across the street as well as the tree that is in front of that house.

You can also see where the sun was when I started the exposure on Sunday, February 15th, 2015 at 9:42 AM Eastern.

The two white squares at the top of the photo is the black tape that I used to tape the photo paper to the inside of the bottom of the can so it wouldn’t move. I wasn’t able to remove it because it would rip the photo paper.

The dark blob at the bottom of the photo is actually the disc of black construction paper that I placed at the top of the inside of the can so the light wouldn’t reflect off of it. It ended up overlapping onto the photo paper just a tad, thus, not exposing that area.

All in all, I think the photo turned out great, and I look forward to building more of these cameras and placing them in random locations around Metro Detroit.