Lunar Eclipse 8-27-26

A lunar eclipse occurs when the Earth’s shadow passes over the Moon, mimicking multiple moon phases in the span of one night. This summer’s lunar eclipse was near-total, with just a small sliver of the Moon visible.

The weather was fairly cloudy, so I shot this eclipse as best I could: sporadically, as gaps in the cloud cover permitted. The photos I ended up with were a little messy (focus and exposure was all over the place, and some phases of the eclipse were fully obscured). Though the data was not the cleanest I’ve ever collected, I was able to get something workable and I enjoyed watching the eclipse.

For this eclipse, I used my signature “close enough” technique for polar alignment. Whenever I can’t see Polaris due to clouds or other obstructions, I just point my polar scope roughly in the direction of the star. At a given latitude, you can just leave the polar wedge’s altitude setting at its usual angle, but there are a variety of ways to align the azimuth. Theoretically you could place a compass on your mount and either just point it north or look up Polaris’s exact magnetic heading for your location. Alternatively, Stellarium shows an alignment circle around an object when you point your phone at it in the sky. I’ve found that if I select Polaris and place the back of my phone normal to the axis of my polar scope, I can adjust my azimuth until the star is centered and I get an easy “close enough” alignment. The “close enough” method will involve some periodic adjustments to recenter the target (unless you get extraordinarily lucky), so it cannot be used for DSO photography. However, for planetary photography and most observing, it is a perfectly viable option. (In fact, some planetary photos like this are shot by recording video of the target drifting across the frame anyway.)

This was my first time creating a planetary animation, and I enjoyed putting it together. To animate the data, I just ran a selection of frames through PIPP. I didn’t preprocess or stack the photos as nearly every shot had different exposure settings and several had clouds moving through the frame. PIPP struggled with registration and alignment of the pictures, largely because PIPP assumes the dark side of the Moon should be facing the same direction in every frame. While the Earth’s shadow was more-or-less toward the bottom of the frame throughout the eclipse, its orientation varied a bit more than PIPP was designed to handle. As a result, the Moon jumps around slightly in frame. After trying every combination of frame stabilization settings, I selected the best output.

Technical details:

• Lens: Sky-Watcher StarTravel 120
• Camera: Nikon D3200
• Mount: Sky-Watcher Star Adventurer 2i
• Optics: N/A
• Filters: mystery Moon Filter I found in my bag
• Exposure: Various
• Corrections: None
• Stacking: None
• Post-processing: PIPP (registration, cropping, and animation)

Notes for improvement:

• Find a better way to align frames
• Data might have been better with 2” optics using my field flattener. I chose 1.25” optics so I could use a filter, but because of the clouds I may have been fine without it. Without a filter to reduce the Moon’s brightness, I could instead step down my aperture.