Photography Workshop Online

Noise is a fact of life in the electronic world; there is no escaping it. Remember audio cassette tapes? Remember those noise charts printed on their labels? Noise is something engineers have wrestled with. Noise is built into all electronic circuits; it’s a physical limitation. The objective is to make the medium (audio tape or imaging sensor) able to capture stronger signal (sound and light) in order to overwhelm the noise in circuits.

Let’s state that in human terms, our imaging sensors have inherent noise, some more than others. In bright light, the signal (light photons) is stronger than the noise, effectively wiping out all visible traces of noise. Noise is still there, but we can’t see it. In low light, the signal is weaker than the noise, effectively wiping out all visible traces of noise. When the signal is weaker, it is not enough to overcome noise, whish is why we see more noise that exposed pixels when shooting in very low light.

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I-Mag Photography

There is one amazing, quite uncanny prediction made by a man called de la Roche (1729- 1774) in a work called Giphantie. In this imaginary tale, it was possible to capture images from nature, on a canvas which had been coated with a sticky substance. This surface, so the tale goes, would not only provide a mirror image on the sticky canvas, but would remain on it. After it had been dried in the dark the image would remain permanent. The author would not have known how prophetic this tale would be, only a few decades after his death.