This month's pic is largely about the science of photography, and how an image is captured on film. This was shot with a pinhole camera.
A pinhole camera - as you may know or be able to guess - uses a tiny hole in place of a lens. It's photography at its most elemental. You may have even used a version to view a solar eclipse.
I won't get all technical discussing apertures / f-stops, but basically an aperture is a hole. A tiny hole, like a pinhole, allows very little to pass through, while a big hole allows a lot through. In terms of a camera, what's passing through is light.
So, for a pinhole camera to capture an image, it takes quite a bit longer for it to get the amount of light it needs through such a small hole.
Picture this...we're driving along a country road in the south of France. It's one of those scenes from a postcard, with tall sycamore trees lining both sides of the road. I take a photo out the back window of the car as we zip along. It's about a three second exposure.
Another interesting thing about a tiny aperture is that it gives a nearly infinite depth of field. In other words, everything is in focus no matter how near or far it is.
So those black lines going across the image are the rear window's defroster lines, just inches from the camera.
If you want to try a neat trick, view this image through a tiny hole (make one with your fingers or poke a piece of paper with a tack or pencil tip), and see what happens.
Oh, and World Pinhole Day is on the last Sunday of April.