This past Monday (Aug. 21, 2017) presented an incredible opportunity to skywatchers in North America. Portions of the United States had a total eclipse of the sun, while in Saskatoon we had approximately 76% coverage. As a fellow science geek I had to get some photos — and possibly even generate a time-lapse video of the event.
Fortunately, the weather conditions were perfect! Here’s the resulting video:
I wound up capturing over 32GB of RAW photographs, about 1/4 of which appear in the above video (I figured 20 seconds was long enough for the time-lapse video).
I used my trusty Canon Rebel T2i camera with an old 85-210mm manual Pentax lens, connected to an adapter for the Canon. The lens was set to 210mm, infinite focal length, and f/22. Attached to the lens were two ND8 filters and an ultraviolet filter. The camera was set to manual mode and exposed the image for 1/4000s at ISO 100. Note: This protected the camera’s electronics for short bursts, but to save your eyes do not look through the viewfinder with just the ND8 filters!
The camera was connected via USB to my MacBook running the Canon EOS Utility software. The Canon utility is fantastic for monitoring what the camera sees on your computer screen, and for taking automated photos at regular intervals. Because eclipses of that magnitude don’t come around these parts all that often, I took a photo every 5 seconds (though as mentioned I used only 1/4 of those for the above video).
Once I captured all the image data I used Final Cut Pro X to create the full video.
Shooting the eclipse
A few days before the eclipse I did a couple of video tests. Here’s one that I shot on a cloudy day that turned out fairly well, rendered in full 4k resolution:
This was shot with the lens at 85mm. One thing you’ll notice is the travel of the sun through the frame. Since I planned to zoom in much tighter on the eclipse day, keeping the sun in the frame was a definite concern.
I ended up shooting the eclipse in 20-25 minute chunks in order to keep the sun in the frame. Unfortunately this means that the final time-lapse video has a few brief jumps as I had to pause the image capture and reposition the camera. Now if I could get a nice sky tracking device for my camera… ?
Nevertheless, watching the progress of the eclipse through my computer screen was quite something. The sky got eerily dark for the time of day (though not as much as it did for those folks who got to experience the total eclipse!). I took occasional screen captures to post the progress on social media. Here is a photo of the eclipse at its greatest coverage:
Creating the video
After transferring all of the still images to an external hard drive I created a new video project in Final Cut Pro and imported everything. With all the images taken together in sequence, I exported a 422HQ video file in 4k resolution, at 4x speed, effectively dropping 3 out of every 4 frames. I decided didn’t want to make an 80 second video, and the next step in the process would be very time consuming: centring each image in the video. Basically, I manually moved each frame of video so the sun was in the centre. This is partly why it flickers around slightly in the final video. I believe I could have used something like Apple Motion 5 to automate the process but it ended up being faster to just do it manually.
The resulting video is also blown up about 200%, and some extra (minor) colour/contrast correction and sharpening is applied. Fortunately, since the original video was created in 4k and the final version is in 1080p I had a fair bit of resolution to play with when I zoomed into the image.
And there you go! I had fun with this and I hope you enjoyed the result!
The video is available on several platforms: