D
Doug Kerr
Guest
This "room" is not ideally chartered to receive this matter, but it seems to have as relevant a portfolio as is currently available
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We often encounter discussions of the dynamic range of a digital camera and how it may be influenced by various design parameters. Often these discussions are hindered by failure to articulate a specific definition of "dynamic range".
The ISO standard for such matters revolves around essentially this definition:
The dynamic range of a digital camera is defined as the ratio between (in a single "shot") the largest uniquely-representable luminance (the "saturation" luminance) and the luminance for which the signal to noise ratio (SNR) of the image is 1.0 (or actually, the luminance at which the SNR would be 1.0, based on a noise level determined at a fixed small luminance, a finesse made necessary by the fact that an actual SNR of 1.0 is "problematical").
I have recently posted to my technical information site, The Pumpkin, a new tutorial article, "The ISO Definition of the Dynamic Range of a Digital Still Camera", available here:
http://doug.kerr.home.att.net/pumpkin/index.htm#ISO-DR
It describes in detail the ISO definition and the tricky way it is defined.
Note that this standard revolves around examination of a digital "image", and this cannot be directly applied to the matter of the dynamic range of a camera from the perspective of its raw output, a matter that introduces a number of thorny issues.
************
We often encounter discussions of the dynamic range of a digital camera and how it may be influenced by various design parameters. Often these discussions are hindered by failure to articulate a specific definition of "dynamic range".
The ISO standard for such matters revolves around essentially this definition:
The dynamic range of a digital camera is defined as the ratio between (in a single "shot") the largest uniquely-representable luminance (the "saturation" luminance) and the luminance for which the signal to noise ratio (SNR) of the image is 1.0 (or actually, the luminance at which the SNR would be 1.0, based on a noise level determined at a fixed small luminance, a finesse made necessary by the fact that an actual SNR of 1.0 is "problematical").
I have recently posted to my technical information site, The Pumpkin, a new tutorial article, "The ISO Definition of the Dynamic Range of a Digital Still Camera", available here:
http://doug.kerr.home.att.net/pumpkin/index.htm#ISO-DR
It describes in detail the ISO definition and the tricky way it is defined.
Note that this standard revolves around examination of a digital "image", and this cannot be directly applied to the matter of the dynamic range of a camera from the perspective of its raw output, a matter that introduces a number of thorny issues.