Friday, October 3, 2008

Sherkin Island National School

Imagine making your own camera out of a shoe box... a coffee can or ...even a teapot?

You can make a camera from anything with a few materials and lots of imagination.

Here are some examples of pinhole cameras made from ;

So how does a pinhole camera work?

We see things because light from the sun is reflected from the surface of objects through the pupil of the eye and an image is created on our light sensitive retina. Brightness and colour is determined by the nature of the object.

A pinhole camera is very like the human eye in the way that it works. It does not have a lens, it only has a very small aperture (hole) through which an image is projected on sensitised material (film or paper).

Light travels in straight lines through the pinhole aperture and is projected onto light sensitive material at the back of the camera.

The human eye works in exactly the same way - but our brain intereprets the upside down image and puts it back up the right way.

Note that the tree is projected upside down.

So is the rabbit!

This diagram shows what the inside of a pinhole camera looks like.

Photographic paper is placed opposite the pinhole and when exposed to light forms an image then it is processed with developing fluids.

Now look at some pinhole images made on Sherkin Island.

Another form of pinhole photography is called solargraphy.

Today we are going to mount some cameras for a solargraphy projectand leave them exposing for a three month period.

We will collect them on December 21st at the Winter solstice when the sun is at its lowest height in the sky. Hopefully the camera will record the sun track as it sinks in the sky.

We will send the cameras to Finland to be part of a global solargraphy project.

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