Eclipse Guide
Eye protection, what to look for, and how to photograph the August 12, 2026 eclipse.
The only safe alternative to naked-eye viewing during totality is glasses specifically manufactured for solar observation. Look for the ISO 12312-2 certification (also written EN ISO 12312-2) printed on the frame — this international standard requires the lenses to block more than 99.997% of visible light and all harmful UV and infrared radiation.
In the European Union, eclipse glasses must also carry the CE mark. Be wary of counterfeits sold at inflated prices near eclipse events: buy from astronomy clubs, planetariums, reputable opticians, or established online astronomy retailers. A simple check: put the glasses on indoors and look at a bright lamp — you should see nothing except a faint, uniform disc. If you can see the room around you, the glasses are inadequate.
Never use: ordinary sunglasses (even stacked), exposed photographic film, CDs, smoked glass, or phone screens held up to the sun. None of these block the full spectrum of solar radiation.
A pinhole projector lets you watch the eclipse by projecting the sun's image onto a white surface — no glasses needed, and the whole family can watch the same image at once.
How to build it: Take two sheets of stiff white card. Pierce a small hole (about 1 mm) in the centre of one sheet with a pin or pencil tip. Stand with your back to the sun, hold the pierced card above your shoulder so sunlight passes through the hole, and project the image onto the second sheet held in front of you. The further apart the two sheets, the larger and dimmer the image. A distance of 50–70 cm gives a clear, watchable image.
Colander method: Hold a kitchen colander between the sun and a white surface — each hole projects a tiny image of the crescent sun, creating a beautiful pattern of crescent suns on the pavement.
Tree shadows: The gaps between leaves in a tree canopy act as natural pinhole projectors. As the eclipse advances, look at the ground beneath a leafy tree — hundreds of crescent suns will appear in the dappled shadows.
A telescope or binoculars will reveal extraordinary detail during the eclipse — but they concentrate sunlight dramatically, making them dangerous without the correct filter.
Always fit the solar filter to the objective (the front, large lens), never to the eyepiece. Eyepiece filters placed at the focal point absorb concentrated heat and can crack suddenly, exposing your eye to the full beam of magnified sunlight. Use dedicated white-light solar filter film (Baader AstroSolar is the standard) cut to fit the front of the instrument.
Safe projection: An alternative is to point an unfiltered telescope at the sun (without looking through it) and project the focused image through the eyepiece onto a white card held behind it. This gives a bright, detailed image and is safe for all bystanders.
Totality is the brief period when the Moon fully covers the solar disc. For observers inside the path of totality on August 12, 2026 (up to 2 minutes and 15 seconds in Salamanca), this is the only time it is safe to look at the eclipse with the naked eye. Remove your glasses the instant the solar disc disappears, and replace them the moment the first bright sliver of the sun reappears.
Attach a sheet of solar filter film over the lens before C2 and after C3. Use manual mode if available: ISO 100, maximum shutter speed. Tap to focus on the sun and lock exposure.
During totality: remove the filter and switch to auto. Point at the corona — the bright inner corona is easy to photograph. Use burst mode. The outer corona is much dimmer and may require a few test shots.
Avoid digital zoom — it degrades quality sharply. Move your feet instead.
Before C2 and after C3: fit a dedicated solar filter (Baader AstroSolar ND 5.0 film is standard). Settings: ISO 100, f/8, 1/500–1/2000s. Test on the partial phases.
During totality: remove the filter. Start at ISO 200, f/8, 1/500s for the inner corona. Bracket widely — the corona ranges over 10 stops of brightness from the inner limb to the outer streamers. Use a cable release or timer to avoid camera shake.
Focal length: 300–500mm gives a solar disc of 3–5mm on a full-frame sensor — enough detail without losing the full corona. Wider lenses capture the darkened sky and landscape in one frame.
Consider putting the camera down for part of totality and simply watching with your naked eyes. The experience of seeing the corona, the 360° twilight and the sudden chill is visceral and unrepeatable.
Many experienced eclipse chasers say their most vivid memories are from the eclipses they watched without a camera. Total solar eclipses visible from mainland Spain occur only once every few centuries — this is a genuinely rare event.
The August 12, 2026 eclipse is a late-afternoon event in Spain (local CEST time). Totality occurs with the sun at approximately 25–30° altitude — still well above the horizon, easy to observe, and ideal for wide-angle photography with landscape and totality in the same frame.
The best viewing locations for maximum totality duration in Spain are Salamanca and Zamora, both near the centreline of the path where totality exceeds 2 minutes. The open meseta landscape offers unobstructed views of the sky in all directions.
August in inland Castile and León has historically very low cloud cover — some of the most reliable clear-sky statistics in Western Europe. However, no weather forecast can be trusted more than a day or two in advance. Have a backup location plan and monitor weather forecasts in the days before.
Sources: NASA Goddard Space Flight Center · International Astronomical Union · American Astronomical Society eclipse safety guidelines