Hi Yulia,
The camera response functions are stored in the text file
$HOME/Library/Preferences/Photosphere
Towards the end, you will see a list of camera responses that have been stored
by make, model, and version. Each line looks something like this:
"NIKON CORPORATION"|"NIKON
D200"|"Ver.2.01"|{-4.765716e-04,1.355876e-01,-1.269868e-01,9.918758e-01}|{-6.390453e-04,1.371893e-01,-1.224765e-01,9.859263e-01}|{-9.074065e-04,1.351222e-01,-1.165654e-01,9.823506e-01}
The coefficients enclosed in curly braces are the polynomial camera responses,
one per color in red, green, and blue order. The coefficient order is from low
to high power, so the above line translates to:
red(r) = -4.765716e-04 + 1.355876e-01*r + -1.269868e-01*r^2 + 9.918758e-01*r^3;
green(g) = -6.390453e-04 + 1.371893e-01*g + -1.224765e-01*g^2 +
9.859263e-01*g^3;
blue(b) = -9.074065e-04 + 1.351222e-01*b + -1.165654e-01*b^2 + 9.823506e-01*b^3
The input (r,g,b) values are camera sensor values normalized in a 0-1 range.
The output values are related to world luminance units, sometimes with a
calibration scaling factor built in.
I hope this is helpful.
-Greg
> From: "Tyukhova, Yulia" <[email protected]>
> Date: October 25, 2011 3:00:13 PM PDT
>
> Hello everybody!
>
> I'm a Fulbright student working on my second Master's in AE Lighting at UNL,
> Omaha. My current research is on High Dynamic Range Imaging in Lighting.
> Does anybody know how to get the information on the response curve from
> Photosphere similar to the one that WebHDR would give you?
>
> Thank you,
> Yulia
> --
> Thank you,
> Yulia Tyukhova
>
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