Eaton Family Solarcan Project - Phase 1: Gifts

My with sister Donna when I was about 4. 

As someone who who has been a shutterbug since I was in kindergarten (Dad let me take one of his cameras on a field-trip to ride a train in Dallas, even coached me to be sure I was pointing the camera ahead rather than straight out the window so everything wasn't a blur) and as someone who has been a science geek for about as long (when my folks asked me what I wanted to be when I grew up, my answer was "scientist"), I get a bit excited when I find something that blends photography and science. 

With that little tidbit, you can probably understand how thrilled I was to discover a product called the Solarcan, a unique camera created to take a solargraph, a long-duration image of the sun's path across the sky, captured by a simple pinhole camera. The unique thing about the Solarcan design is that there is no negative... the image is captured directly on light-sensitive paper and to "develop" it you just take the paper out of the can and scan it into your computer.

Example of a solargraph by Chuck Miller (flickr)

Given that the Solarcan design is just an aluminum can with a pinhole in it and a piece of photographic paper tucked inside, you might wonder why not just make one on my own. Sure, I could have followed directions readily available online such as these on Instructables. That would have been fine if my goal was to experiment for a few months to work out the right configuration of materials, get the pinhole just right, etc. But I had more immediate plans: I wanted to share this with my grandkids for Christmas. 

So I ordered a 5-pack from Solarcan in early December. They arrived a week ahead of Christmas, perfect timing to shoot one for a week (as it happens, spanning the winter solstice) with the other four wrapped as gifts for four of my five grandkids. The fifth, Owen, is just over a year so not old enough yet for a "Papa project" like this. 

Eaton Solarcan #1  

Although the ideal timeline for a solargraph is to leave it up for about 6 months, from solstice to solstice, so that the sun traces lines across the image from its lowest path in the winter through its highest path in the summer, I figured that at least capturing a week would provide enough suntracks to illustrate what a solargraph could look like. 

On Christmas Day, with all our kids and grandkids over for Christmas dinner, I took Kaili, Jack, Olivia and Harper out back to show them the Solarcan I had installed the prior weekend, oriented towards the south with a view of our back yard. My plan had been to have them help remove the paper from the can, scan it and play around with the results in Photoshop to clean it up. Unfortunately, our can opener wouldn't work with the "beer can" style rim on the Solarcan. However, the following week I got a can opener that worked, "developed" the image and here is the result. 

Not bad for a first pass. I was pleasantly surprised at the amount of foreground detail captured and although the sun tracks from day to day kind of run together, it's definitely wide enough to tell this was shot over more than just a single day. 

That said, there were plenty of lessons learned including:

• I was a little off in aiming the pinhole so the arc of the tracks the sun traced across the image are shifted to the left. 
• There is a shadow on the lower left that is from the tab that holds the paper in the can. Next time, doing a better job aiming towards the point of the mid-day sun, we should have the arc of the sun centered and can crop out the retainer tab shadows. 
• I think when I finally opened the top of the can, the room might have been a bit too bright which may account for the streak from the left side up towards the top. Something else to be more careful about. 

I'll follow up with additional posts on helping each grandkid to set theirs up and later in the year what the results they get look like. I also have a smaller solargraph from Solarcan called a Puck so I'm looking for a unique spot to set it up for half a year or so. 

Stay tuned!

Rough Draft: Timelapse of Longest Lunar Eclipse in 1000 Years

As mentioned in my last post, I used my Nikon D750 DSLR mounted on a Sky-Watcher Star Adventurer tracker to capture about 5 hours of the partial lunar eclipse. Here is a preliminary time lapse video. 

This sequence is just from the shots exposed for the sunlight face of the moon. I'm working on another sequence with full lunar surface, blending shots exposed for sunlight and shadow. The blended shots will showcase the redness of the lunar surface at mid-eclipse. They will also include the Pleiades and a tighter crop. 

The movement of the moon in this sequence is not due to its movement across the sky but the moon drifting out of center-frame due to the polar alignment of tracker being a little bit off. I'm still working on a process to re-align the sequence and to rotate the view for a more natural orientation of the sky.

When watching the video, be patient as there are a few seconds in the middle where it goes black. The shots used in this video were taken at f/6.3, 2500th of a second, ISO 800. It turns out that was slightly underexposed for a sunlit lunar surface during the phase where the Moon was mostly eclipsed, I missed capturing the portion of its surface still reflecting sunlight so nothing shows up.  

More to come...

BTW, for a better view, select full screen (box icon, lower right) when playing the video. 

Chasing A Partial Lunar Eclipse and the Seven Sisters

In the early morning hours of November 19, 2021, a lunar eclipse began. As a partial eclipse, it normally might not have been noteworthy. What brought a lot of media attention about this one is that it lasted just a shade over 6 hours. It's been 1000 years since the last time a lunar eclipse lasted that long. 

The timing for this eclipse is such that the Moon was almost at apogee, the point where it is furthest from the Earth in its orbit, and since a body in orbit moves slower the further it is from the body it orbits, the Moon spent more time in Earth's shadow. It also meant that the Moon was smaller in appearance so this was the opposite of a "Super Moon". 

The other interesting thing about this lunar eclipse is that the Moon is within a few degrees of the collection of stars known as the Pleiades or the Seven Sisters. As both were high in the sky during most of the eclipse, the cold dry air we had in North Texas that night made for great viewing. 

Initially, my plan to capture the eclipse was to shoot with my Nikon D750 using the longest lens I have and the Star Adventurer sky tracker to capture shots of the lunar face throughout the night to create a timelapse video. However, given the close proximity of the Pleiades, I decided to shoot with a shorter lens and include it in the view. 

I won't go into the technical details but given this was really the first time I had used the Star Adventurer for tracking more than a few minutes, I shot a bit wider view than I probably needed to so the Moon is rather small in the frame. The bad news is that the tracker was a little off and so the Moon didn't stay centered in the frame. The good news is that with the wider view, both it and the Seven Sisters were in-frame throughout the 5 hours of the eclipse I captured. 

Here is a frame from about mid-eclipse. I'll post more as I get further through post-processing all the images.