But most of our respect should be paid to Giovanni Antonio Canaletto. As a painter he used the principle of the camera obscura in a very practical and commercial application. Although he did not take photographs as one understands it today, he imaged scenes and objects on canvas through a narrow hole in a curtain and  painted them. With the help of this technique he was able to produce more than 900 paintings during his period. Later Giovanni Battista Della Porta suggested for the first time that a lens may be applied to the hole. This was the initial step for the invention of the portable “camera obscura” as a working tool for  outlining at that time.

In the frame of this experiment a high performance industrial CCD zoom camera with USB computer connection is applied. Parameters like diaphragm size, position and the influence of lenses on the brightness, sharpness and dimensions of the image are investigated. The variable diaphragm demonstrates the effect of depth of field. Furthermore a LED emitting invisible radiation to the human eye is provided to study the exciting technology of active night vision.