The odd and beautiful pinhole effect - pictures and explanations.

I had the chance to see it during the total eclipse of the sun in 1999; unfortunately, I was so wrapped up by the spectacle of the obscured sun itself that I haven't thought at the time to take some shoots.

During the last eclipse this week, some fellow astronomers haven't done the same mistake:




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When the sun’s rays hit the ground passing through small gaps between tree leaves, they create the “Pinhole Camera” affect. These are actually small inverted images of the sun projected on the ground.




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A pinhole camera is a simple camera without a lens and with a single small aperture – effectively a light-proof box with a small hole in one side. Light from a scene passes through this single point and projects an inverted image on the opposite side of the box. The human eye in bright light acts similarly, as do cameras using small apertures.

Up to a certain point, the smaller the hole, the sharper the image, but the dimmer the projected image. Optimally, the size of the aperture should be 1/100 or less of the distance between it and the projected image.

Because a pinhole camera requires a lengthy exposure, its shutter may be manually operated, as with a flap of light-proof material to cover and uncover the pinhole. Typical exposures range from 5 seconds to several hours.

A common use of the pinhole camera is to capture the movement of the sun over a long period of time. This type of photography is called Solargraphy.

Pinhole camera

How to make a pinhole camera?

Check out also this wonderful gallery:

Tree Leaves as “Pinhole Cameras” During a Solar Eclipse


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The pinhole effect is an equally effective way of watching the eclipse because it allows people to follow the eclipse’s progress by projecting the sun’s image through a small hole, such as that made by a hole-punch in a piece of card, and follow the changes on the ground.


Eclipse through a bathmat

And let us also not forget that this is also a cheap method of being able to see the upcoming transit of Venus.

Its what I did last time.

reply to post by elevenaugust


Good thread, and that first pic is great. I discovered this effect by "accident" just by looking at the ground during an eclipse in the mid '90s. And I like the idea of using this method for the venus transit.