A pinhole camera is the simplest camera possible. It consists of a light-proof box, some sort of film and a pinhole. The pinhole is simply an extremely small hole like you would make with the tip of a pin in a piece of thick aluminum foil.
A pinhole camera works on a simple principle. Imagine you are inside a large, dark, room-sized box containing a pinhole. Imagine that outside the room is a friend with a flashlight, and he is shining the flashlight at different angles through the pinhole. When you look at the wall opposite the pinhole, what you will see is a small dot created by the flashlight's beam shining through the pinhole. The small dot will move as your friend moves his flashlight. The smaller the pinhole (within limits), the smaller and sharper the point of light that the flashlight creates.
Now imagine that you take your large, dark, pinhole-equipped room outside and you point it at a nice landscape scene. When you look at the wall opposite the pinhole, what you will see is an inverted and reversed image of the scene outside. Each point in the scene emits light, and, just like the flashlight, the beam of light from that point passes through the pinhole and creates a point of light on the back wall. All of the points in the scene do that at the same time, so an entire image, in focus, is created on the back wall of the room. The image is very dim because the pinhole is so small, but you can see it if the room is very dark.
Friday 29 January 2010
PINHOLE CAMERA research
A pinhole camera is a very simple camera with no lens and a single very small aperture. Simply explained, it is 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. Cameras using small apertures and the human eye in bright light both act like a pinhole camera.
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 screen.
A pinhole camera's shutter is usually manually operated because of the lengthy exposure times, and consists of a flap of some light-proof material to cover and uncover the pinhole. Typical exposures range from 5 seconds to hours and sometimes days.
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.
The image may be projected onto a translucent screen for real-time viewing (popular for observing solar eclipses; see also camera obscura), or can expose film or a charge coupled device (CCD). Pinhole cameras with CCDs are often used for surveillance because they are difficult to detect.
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 screen.
A pinhole camera's shutter is usually manually operated because of the lengthy exposure times, and consists of a flap of some light-proof material to cover and uncover the pinhole. Typical exposures range from 5 seconds to hours and sometimes days.
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.
The image may be projected onto a translucent screen for real-time viewing (popular for observing solar eclipses; see also camera obscura), or can expose film or a charge coupled device (CCD). Pinhole cameras with CCDs are often used for surveillance because they are difficult to detect.
lens based
-we used normal digital cameras in this and blurred the image to create many layers on one image.
-we rubbed out the pieces of layers that we never wanted to be shown to create a better image with the beneath layrs showing through.
Subscribe to:
Posts (Atom)
