Monday, February 16, 2009

Pinhole "Lens"

The Pinhole camera or Camera obscura is the most primitive camera, invented about a thousand years ago. It was a simple device, basically a light-proof box, big enough to sit inside, with a small hole to let light enter and project an image onto the opposite wall. At first, recording of the image was done by manually tracing the projected image. A less manual method of recording was not discovered for another 600 years.

I made a pinhole "lens" for my modern camera. Although it's not really a lens, because it has no glass. I took the lens mount from my extension tubes and cut out a piece of cardboard to fit snugly inside. Then I got a pin and made a hole in the middle and attached it to my camera. The smaller the hole the clearer the picture. My first attempt at a hole was too big, the pictures were quite blurry. The cardboard was too thick to make a good, small, clean-cut hole all the way through, so I removed a larger piece of the cardboard and then covered the space with aluminum foil, since it's very thin and blocks 100% of light. Then, with the cardboard laying flat on a table, stuck the pin in again. This way I got a hole that was only the size of the tip of the pin. The pictures are still a bit blurry, but good enough, I guess. The depth of view seems to be infinite, there's never a need to worry about focus. Objects near and far look the same. Due to the small amount of light, all these pictures needed a 20 - 30 second exposure. Below is the first attempt:


I'm not really sure if there's any point to all this. It makes for an interesting effect, although, you could probably get the same effect by editing the picture afterwards. I just thought it was a cool experiment, it makes you think a little bit about how light and cameras work and how easy it is to take a picture now compared to long ago.

Here's some with the smaller hole. For some reason the dust on my sensor becomes very visible when using the the pinhole lens, not really sure why. I've never cleaned my camera since I got it 3 or 4 months ago. I should learn how to do that sometime.





3 comments:

  1. Really nice images. I especially like the last one. There probably is a way to do the same thing on the computer, but then that's NOT photography, it's graphic arts. I'm of the thinking that special effects should be done "in-camera". But I know that many others disagree with me. Good for you for experimenting.

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  2. Re: Cleaning the sensor. Get yourself a rocket blower. It is effective and safer than a swab.

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