On Jul 14, 9:12 am, "Mark Shelley" wrote:
In the film world ISO is the sensitivity of the film to light. In the
digital world it still represents the sensitivity of the whole camera to
light.

The CCD sensor essentially captures photons in each pixel and then converts
this into an integer representing the brightness of the equivalent image
pixel. Think of it like this:

image pixel brightness = (number of photons) x ISO x (some camera
constant)

The higher the ISO, the brighter the image i.e. the increased sensitivity of
the camera to light. The downside is that the higher you push the ISO, the
noisier the image becomes - this is also analogous to the world of film.
The noise is partly due to inherent weaknesses in the film or in the CCD
sensor and it is partly a limitation resulting from the physics of image
formation.

Mark

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I understand the concept of "ISO" within the context of camera film
what I don't understandis the meaning in the context of a digital
camera. What occurs when the ISO setting is changed (increased to
higher speeds) assuming that one is in Manual Mode?

Thanks.

Larry- Hide quoted text -

- Show quoted text -

Mark:

Thanks. Your first sentence "In the film world ISO is the sensitivity
of the film to light. In the digital world it still represents the
sensitivity of the whole camera to light." highlights my lack of
understanding. What aspect of digital camera when I increase ISO. In
Manual Mode, I set the exposure time and aperture value. What changes
when I increase the ISO setting?

Thanks.

Larry