i wnat ppt of automatic camera for mechatronics project.its components and working..
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automatic camera ppt
Automatic Cameras
Automatic cameras are highly trustworthy and can produce consistently good results, as long as you understand them. The problem is that automatic cameras are easily fooled. If there is also a fool trying to use it, results become highly variable. The cameras have little intelligence, relying for that upon the user. Here are some "Gotchas!" and how to avoid them.
Auto-exposure
The camera seeks an average. Photograph a black card, a middle grey card and a white card, and you end up with three grey cards. It increases the exposure with the black card, in order to achieve the average and decrease the exposure with the white. Only the grey gets correct exposure.
I recall a message in a forum that clearly reflected this. The writer was trying to photograph some pieces of jewelry on a white background, but got grey instead of white.
He tried a more intense light and still got grey. Finally he tried shooting it in full sunlight and once again the same tone of grey, so he decided his camera must be defective.
It was simply acting as any camera would under the circumstances. Every time he increased the level of light, the camera compensated by shortening the exposure. The solution was to either use the camera's exposure compensation adding 2EV or by adjusting the histogram by using levels in an image processing program.