This short video provides an introduction to lunar eclipse planning in The Photographer’s Ephemeris Web:
Planning a Lunar Eclipse Shoot in TPE Web
A total lunar eclipse occurs when the full Moon passes through Earth’s shadow. Unlike a solar eclipse, a lunar eclipse is visible from anywhere on the night side of Earth. However, the timing, altitude, and orientation of the Moon vary by location. Careful planning will help you determine when the eclipse is visible, where the Moon will appear in the sky, and what type of photograph is feasible.
TPE Web provides eclipse contact times in Map view and a detailed visualisation in the Moon Simulator. For an overview of the simulator controls and display options, see Planning with the Moon Simulator.
Eclipse Terminology
A few terms will help you interpret contact times and follow the eclipse as it unfolds in the Moon Simulator.
- Penumbra: The outer portion of Earth’s shadow. In the penumbra, Earth blocks only part of the Sun’s light. The dimming is subtle and often difficult to perceive.
- Umbra: The inner, darker portion of Earth’s shadow. In the umbra, Earth completely blocks direct sunlight from reaching the Moon.
- Penumbral eclipse: Occurs when the Moon passes only through the penumbra. The effect is mild shading across the lunar surface.
- Partial eclipse: Occurs when part of the Moon enters the umbra. A distinct dark “ bite ” appears on the lunar disk.
- Total eclipse (Totality): Occurs when the entire Moon is inside the umbra. The Moon may appear red or copper-coloured due to sunlight refracted through Earth’s atmosphere.
- Umbral magnitude: A measure of how deeply the Moon is immersed in the umbra. Values near 1 indicate the start or end of totality. Larger values indicate the Moon is deeper within Earth’s shadow and may appear darker.
Checking Eclipse Visibility & Timing
To plan an eclipse shoot for your location, start with the Map view in TPE Web:
- Set the date to the day of the eclipse (or find it for your location using the “ Events ” menu).
- Place the primary pin at your shooting location.
- Use the eclipse contact markers in the time bar to jump between key stages.
Contact labels include:
- P1 – Start of penumbral eclipse
- U1 – Start of partial eclipse (Moon enters umbra)
- U2 – Start of totality
- Max – Maximum eclipse
- U3 – End of totality
- U4 – End of partial eclipse
- P4 – End of penumbral eclipse
Click the event in the Timeline to set the time to that moment or hover over the event for additional details, including a photography tip.
The following factors will shape the type of shot that you can make:
- Moon altitude (degrees above the horizon)
- Azimuth (compass direction)
- Sky brightness (night, twilight or near sunrise/sunset)
Using the Moon Simulator to Explore the Eclipse
To visualise the progression of the eclipse, expand the Moon Simulator to full view. Once there, enable Shadow Rings to display Earth’s shadow.
- The yellow ring represents the penumbra.
- The red ring represents the umbra.
As you step through contact times or use playback controls, be sure to observe:
- The progression from penumbral shading to partial eclipse.
- The transition into totality.
- Changes in brightness and contrast.
- Sky brightness during the event.
The simulator also displays umbral magnitude, which increases toward totality and decreases afterward.
Evaluating altitude, azimuth, and sky brightness
Altitude
Low-altitude eclipses are often easier to pair with landmarks such as buildings, ridgelines or mountains. However, haze and atmospheric distortion may reduce clarity.
High-altitude eclipses are less suitable for foreground alignment but may favour telephoto or sequence compositions.
Azimuth sweep
The Moon changes azimuth during the eclipse. In some locations, it may move 70–80° across the sky between P1 and P4.
If you plan to capture a composite sequence, note the azimuth and altitude at key stages to determine whether a single framing can accommodate the entire progression.
Sky brightness
Eclipses may occur:
- Shortly after moonrise
- Overnight in a fully dark sky
- Near moonset at dawn
Twilight can reduce contrast, especially during penumbral and early partial phases. Totality remains visible but may have lower contrast in civil twilight.
Location examples
The following examples highlight how location impacts shooting conditions and what might be possible at your location – assuming clear skies!
Hobart: Evening eclipse
In Hobart, the eclipse begins shortly after moonrise. The Moon is low above the horizon during early phases, offering opportunities to include foreground elements.
However, at the start of the penumbral phase:
- The sky may still be bright.
- The contrast is low.
- Haze near the horizon may obscure detail.
As the sky darkens and the Moon climbs higher, partial and total phases become more visually distinct.
Vancouver: Overnight eclipse
In Vancouver, the eclipse occurs overnight. The Moon is already high in the sky when partial phases begin.
This reduces opportunities for landmark juxtaposition. Consider:
- A telephoto composition
- A multi-frame sequence showing eclipse progression
- Architectural elements that remain illuminated at night
Note that while totality timing is identical globally, the orientation of the brighter limb relative to the observer varies by location.
Minneapolis: Eclipse at moonset
Further east, the Moon may set during partial or late phases of the eclipse.
In such cases:
- Totality may occur during twilight.
- The sky may brighten toward sunrise.
- The eclipse may end below the horizon.
Use the simulator to confirm whether all phases are visible at your location.
Tips for Photography
Acquire focus during partial phases. High-contrast edges during partial eclipse make autofocus easier. During totality, the Moon is much darker and more difficult for autofocus systems to lock onto. Avoid refocusing during totality unless necessary.
Expect significant exposure differences. The brightness difference between partial phases and totality is substantial. Exposure settings suitable for a bright partial Moon will not be appropriate during totality.
Plan for movement across the sky. If creating a composite sequence, record altitude and azimuth at key stages to determine the required horizontal and vertical framing.
Consider atmospheric effects. Low-altitude shots may include haze, distortion or colour shifts.
Other types of lunar eclipses
Not all lunar eclipses are total.
Penumbral eclipses The Moon passes only through the penumbra. The effect is subtle shading and may be difficult to detect without careful observation.
Partial eclipses Only part of the Moon enters the umbra. A distinct shadowed portion is visible, but totality does not occur.
The Moon Simulator visualises all eclipse types using Shadow Rings and contact markers, allowing you to evaluate visibility and geometry at any location.
Notes
- Totality timing is the same worldwide, but altitude and azimuth differ by location.
- The orientation of the brighter limb during totality depends on your observing position.
- Twilight and moonset may limit visibility at some locations.
- Subscription tier limits apply to date navigation (PRO: full access; Supporter: 5-day look-ahead; Free: 24-hour look-ahead).
Using TPE Web and the Moon Simulator together allows you to evaluate eclipse timing, geometry, and composition opportunities before heading into the field.
