Safety
Certified eclipse glasses
An ISO 12312-2:2015 filter is not a pair of sunglasses. Improvising can permanently damage the retina.
Will not do
Sunglasses
Not polarised, not category 4, not two pairs stacked. They still pass too much infrared and visible light.
Will not do
X-ray film
A hospital plate is not a solar filter. No test, no CE, no margin.
Will not do
Smoked glass
Bottle glass, a welder’s leftover, a photo negative. They darken; they do not filter what must be filtered.
Use
How certified glasses are used
01
Before
Inspect the polymer. If it is scratched or holed, do not use it. Put the glasses on before you look at the sun.
02
Partial phases
While any part of the Sun is visible, the glasses stay on. Do not use them with telescopes, binoculars, cameras or any other optics.
03
Totality
Only with the disk covered. As soon as light returns, the filter returns to the face.
Only in totality, without a filter.
When the disk is fully covered — and only then — the glasses can come off and you may look at the corona with the naked eye. The second diamond means they go back on. If you doubt, leave them on.
IGN times for Cádiz, Málaga, Ceuta and Melilla are on the 2027 eclipse map. More answers are in the FAQ.