Many digital cameras support video capture, enabling documentation of eclipse-related phenomena through simple setup rather than complex instrumentation.
General Setup Principle
- For several projects, a tripod is helpful for stability. When multiple experiments are conducted, a shared tripod may reduce logistical complexity.
Camera Caddy (Reduced Setup Complexity for Multiple Projects)
- A camera caddy provides multiple camera mounts on a single stable platform, simplifying deployment and reducing the need to acquire additional tripods.
Build Summary
- Start from a thick board (e.g., 7½ inches square, ¾ inch thick).
- Round the board selectively to minimize weight.
- Drill a central opening and additional screw/fastener mounting holes near the perimeter.
- Install a threaded bar with drilled and tapped holes to which mounting posts attach.
- Use compact ball-head mounts (with ¼–20 threaded connections) to hold camera positions.
- Sand edges to minimize injury risk.
Record the Darkening
- This project documents eclipse intensity changes as the scene darkens and then re-brightens.
Key Controls
- Select a fixed viewing “spot” area and frame the camera so it records the observer.
- Begin recording at a predefined time before totality (e.g., 10–15 minutes).
- Record for an equal interval after totality.
Critical camera settings:
- Disable or account for exposure compensation features that try to brighten a darkening scene.
- Ensure sufficient storage for a total recording duration (e.g., 20–30 minutes).
- Confirm battery charge and have a spare battery if needed.
Record the Shadow Passing Overhead
- This requires cloud conditions or clear visibility of the approaching shadow.
Procedure
- Point the camera toward the direction the shadow will approach relative to your location, or toward the travel direction if clouds are present.
- Use the same recording logic as the darkening procedure (start earlier and stop later).
- For the 2017 eclipse, the shadow path moved across the U.S. from northwest to southeast; thus, location relative to that axis determines camera direction.
Record the Temperature Drop
This requires:
- a digital thermometer (preferably without auto-display shutoff for short intervals),
- a digital watch/clock (analog is allowed but reduces timing precision),
- optional shading of the thermometer from direct sunlight to improve measurement accuracy.
Two approaches exist:
- Record a continuous time series via video (without a tripod if balanced on a stable surface).
- Use camera interval capture (if supported) to effectively speed up playback by capturing frames at fixed seconds intervals rather than full continuous video.
- Record Shadow Bands
- Shadow bands occur infrequently and appear as undulating parallel lines shortly before or after totality. They are caused by refractive phenomena in the atmosphere associated with the thin solar crescent during the eclipse.
Recording Method
- Mount a video-capable camera on a tripod.
- Point at the ground surface.
- Record over a window spanning several minutes before and after totality (e.g., 5 minutes before and 5 minutes after).
Enhancing Probability
- Use a bright target region on the ground.
- Some observers increase visibility by stretching a white sheet or blanket on the ground and pointing the camera there.
- Anchor the sheet securely against wind using multiple weights distributed along edges, not solely at corners.
- Get to the Center Line (Maximize Totality Duration)
- The central operational priority during eclipse planning is reaching the path of totality. Additionally, positioning on the center line maximizes duration.
Rationale
- The Moon’s shadow is approximately circular during totality.
- The duration depends on the path length of the shadow’s intersection with a given Earth location.
- Being on the center line corresponds to the longer chord intersection of the shadow, producing the longest totality.
- Implication
- At the extremes of the totality path, the intersection becomes very short; in idealized cases, observers may experience less than a second of totality.
