Eclipse 2026

12 Aug 2026 · Moon covers Sun, mostly.

Moon covers Sun, mostly.

Every now and again in the celestial dance the sun, moon and earth line up in such a way that the moon covers the sun when viewed from earth. Well on the 12 August 2026 one of those alignments happened to occur over the skies of the UK. The last time it happened was in 1999, a quick google tells me it was on August 11th. I was stood outside of a now long since closed paper mill in Lancashire looking through a welding glass (I'm told this isn't safe and you shouldn't do it, my eyes are fine, YMMV). I recall the skies going dark, nature going quiet (the paper machine was off at the time, so I could hear nature) and everyone involved being collectively moved by the event.

Naturally when I heard that one was happening again I wanted to make sure to enjoy it again. This year's summer has been warm and dry in the UK, and 12th August was no exception, the skies were clear and cloud free, perfect eclipse watching conditions. I thought about welding glass, I thought about eclipse glasses and I figured I had time to build a pinhole camera. This is my story of the eclipse.

Reality Check

When you see an eclipse on the TV in films it's either CGI or someone has spent many many hours preparing thousands of pounds worth of equipment. When you see one for yourself, it won't look like the TV. Although the sun is massive, it's quite a long way away, so any image you capture of it will be quite small, you'll not see the sun's corona. The size was one of the things I wanted to try and fix with the pinhole camera.

Goals of the exercise

Make the image bigger
Make sure nobody goes blind
Make it easy to see
Make it easy to photograph
Do something cool and sciencey with Mitch

I started with some rough maths. The sun is a teeny bit more than half a degree (0.53) wide in the sky. 0.53 degrees = 0.00925 radians. 3.5x0.00925 = 0.0324 (meters), so if I could make a pinhole camera who's "screen" was 3.5m away from the "lens" then the image should be about 32mm wide. I rooted about in the garage and the blue bin and figured we had enough thick cardboard to make a tube roughly the size of a sheet of A4 paper about 3.5m long. Perfect.

Problem 1 (tiny image) solved.

A pinhole camera works by taking advantage of the light travels in straight lines rule. A pinhole camera is a dark space with a tiny opening at one end (the pinhole, which is literally a hole made by a pin) and a projection surface at the other end. There's a balance to be struck with the size of the hole. If the hole is larger then more light gets in, but the image looses sharpness. Too small and the image is sharp but less light gets in so the image is dull. I found a push pin was just right, a sewing needle was too small.

Anyway, the light from the sun passes through the hole which sorts the rays by direction and turns angle in the sky into position on the screen. By projecting the image onto a screen I removed all the risks associated with looking directly at the sun.

Problem 2, solved. The third goal - make it easy to see, was very simple. Cut a flap in the tube so we can look into it. No closing one eye just look into the hole and point the other end at the sun. A 3.5m cardboard tube is quite cumbersome, the empty brown bin made a perfect pinhole camera monopod.

Problem 3, solved.