Watch the eclipse. Keep your eyesight.

Why this is not optional

The Sun’s focused light burns the retina — the eye’s sensor — in seconds. The retina hasno pain receptors: you feel nothing while the damage happens, and the blind spot or blur (solar retinopathy) appears hours later. It is often permanent. A 92%-eclipsed Sun, like the one over Paris, is still far too bright to look at: the remaining sliver carries full surface brightness.

Eclipse glasses: the one thing to get right

• Look for the ISO 12312-2 certification printed on the glasses — it is the international standard for direct solar viewing.
• Buy from reputable astronomy retailers, planetariums or science museums — not from unverified marketplace sellers.
• Inspect before use: any scratch, pinhole or crease means the pair goes in the bin.
• Glasses from the 2024 American eclipse are fine if certified and undamaged.
• Regular sunglasses — even several pairs stacked, even category 4 — block nowhere near enough light. Never use them.

Children

Kids’ eyes let in more light than adults’ and the risk is higher. Fit their glasses well (adult sizes often don’t seal on small faces), supervise constantly, and prefer projection methods for younger children — they’re just as magical and completely safe.

Cameras, binoculars and telescopes

Optics concentrate sunlight: pointing them at the Sun without a filter destroys sensors and can injure eyes instantly — eclipse glasses behind an eyepiece are not protection; the focused beam melts them. The filter must go on the front of the instrument:

• Cameras & smartphones: a certified solar film or filter over the lens for all partial phases.
• Binoculars & telescopes: purpose-made front-aperture solar filters only. No “solar eyepieces” — they’re dangerous and long banned.
• Smart telescopes: the safest way to observe details like sunspots — instruments such as Unistellar telescopes fitted with their Smart Solar Filter find and track the Sun automatically, and you watch on a screen instead of through an eyepiece. No direct optical path to your eye at any point.

No equipment? Project it

• Pinhole projector: a small hole in cardboard projects a crescent Sun onto any surface a metre or two behind.
• Kitchen colander: dozens of little crescents at once.
• Tree shade: gaps between leaves act as natural pinholes — the ground fills with crescents. The classic eclipse photo nobody expects.

All projection methods share one rule: you look at the projection, never through the hole.

The totality exception

Inside the path of totality (western Iceland, northern Spain), when the Moon covers 100% of the Sun, protection can come off: totality is safe — and breathtaking — to watch with naked eyes. Two hard limits:

• Only between the “second contact” (last flash of sunlight, the diamond ring) and “third contact” (the diamond ring returning). On this eclipse that’s at most ~2 minutes — set a timer.
• This never applies outside the path. In France, Germany, the UK — anywhere the eclipse is partial — protection stays on for the entire event.

Never use

Smoked glass, CDs/DVDs, X-ray film, photographic negatives, space blankets, welding glass below shade 14, polarizing or ND camera filters held to the eye. All of these transmit invisible infrared or ultraviolet light that burns the retina even when the visible glare seems comfortable.