A bit of a story behind the image:
The eclipse in south-east England was due on Saturday 29 March 2025 from 10am to midday. Only late on the previous evening did I realise it was coming. The sky had been clear for some days and the forecast was good. The next eclipse is August 2026, then no more until 2090, so this may be my last chance of a decent eclipse photo. I put the camera battery on charge.
I have a telescope that can act as a 2000mm lens on the camera, but the scope is packed away, so probably not enough time to dust it off, set it up, test it, and so on. So I’ll use an ordinary lens, capturing a series of images I can glue together.
Some quick calculations: in two hours the sun travels 30 degrees across the sky, and a 50mm lens on full frame (36mm x 24mm) covers a horizontal angle about 40 degrees, so that will capture the entire event.
Every 5 minutes the sun travels 1.25 degrees, and the sun’s diameter is 0.5 degrees, so 5 minute intervals gives a good but not excessive separation. How do I time the exposures? I don’t have a watch or phone, and only one clock that only works sometimes. I could use the laptop, but that would be a nuisance. Hang on – the camera has a clock, but I don’t think it can show it when it is also ready to take a photo. Hang on again, doesn’t it also have an intervalometer? I read the manual. Yes, I want the “interval timer” features which takes a still photo at fixed intervals, not the “time-lapse photography” which makes a movie one frame at a time, at fixed intervals. (I’d like a movie from which I could extract frames, but on this camera (Nikon D800) movie frames have only 1920x1080 pixels.)
How many pixels wide will the sun be? The camera makes images 7378 pixels wide. On the sensor, the sun will be approx tand(0.5)*50=0.436 mm wide. There are 7378/36 pixels/mm, so sun is tand(0.5)507378/36 = 89.4 pixels wide. That is enough to clearly see the sun’s circle being “bitten” by the moon.
Time is getting on. If I go to bed, I’ll probably wake up too late. So I have a short snooze, and then some food to keep me going.
At 06:25, the camera says the time is 07:34. I bought the camera in the summer and have never fiddled with the clock because I have never before cared about the exact time a photo was taken, so it has gained 9 minutes in 13 years. Not bad. I correct the camera’s clock.
At 7am, the sun has risen. I take a photo at f/32 1/8000 second, and upload to the computer. The sun’s disk had saturated the sensor, unsurprisingly, but so has an area around the sun. My colour filters are fairly handy, so I try them, and this reduces the over-exposure.
Okay, now I need an interesting foreground. I’d like to include the local red telephone box as it is due for removal, but it is adjacent to a bus shelter so I can’t get it and the sun in shot. The playground has a good selection of climbing frames, so I choose one and position the camera on the tripod, shifting around to get what I hope will be a good composition with multiple positions of the sun.
Satisfyingly, the camera does a clink-click at exactly 10am, and another at 10:05. I settle into the book I have brought with me. Then the clouds arrive, and the sun becomes hazy, practically invisible. I consider giving up.
A man arrives with three young girls who chase each other around the playground. One of them thinks my tripod must be for fun, and makes a grab for it. I politely but firmly ask her not to touch it. Thankfully she complies. Even better, her father doesn’t punch me.
10:50 slightly before maximum eclipse, the haze reduces. I’ve brought some white paper, and a thick black paper with a pinhole. Projecting the sun through the pinhole to the white paper clearly shows the “bitten” sun. This is the first definite proof that I’ve come on the correct day. I am greatly relieved. I show this to the man who says it is “cool”. We show it to his daughters who are totally unimpressed.
12:05 The final photograph. The sun has moved out of frame, so I won’t use this one. I take some photos with normal exposures for the foreground. (I later find I have fluffed the exposure for these, burning out the cloud top-right.) The man and daughters have departed. I pack up and go home, and collapse into bed.
I explained above how I made the final image. I like the strong composition. With hindsight, I would prefer the left-most sun closer to the left-hand post, either by having the camera in a different position or by starting the first exposure earlier. Of course, I could fiddle it either by moving the composite of all the suns leftwards with respect to the background, or duplicating the left-most sun. And I could tilt the path of the suns to be parallel to the cross-beam. But that would be dishonest, in a sense. Too dishonest for my taste. And it might become over-prettified. It is what it is.
