> On 13/12/06, Cory Papenfuss <[EMAIL PROTECTED]> wrote:
>>         Now, for example, if one were to apply a cloudy WB vs. a tungsten
>> WB, the red channel gain would likely be at least a bit (i.e. f-stop) or
>> two different.  It makes sense to chose a different "dynamic range" for
>> each channel based on things like WB (and by association colorspace).
>
> Just being pedantic but you allude in the above paragraph that
> Colorspace is dependent on "dynamic range" however it's not,
> inappropriate choice of WB may cause some colours to clip in certain
> circumstances but it doesn't alter the sensors colour response. Just
> consider the scenario of a sensor which has acute sensitivity to near
> UV and near visible IR but very poor green response. It could feed
> into a 4 bit ADC but would still require a very wide colorspace to
> adequately describe/contain it's colour response.
>
        Isn't this whole discussion pedantic?  :)

        What I *meant* to say was the the per-channel transfer function 
from input to output is a function of WB and colorspace.  Once the output 
has to be truncated to 12-bits, those parameters now affect the output 
dynamic range.

-Cory

  --

*************************************************************************
* Cory Papenfuss, Ph.D., PPSEL-IA                                       *
* Electrical Engineering                                                *
* Virginia Polytechnic Institute and State University                   *
*************************************************************************


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