scott <sco### [at] scottcom> wrote:
> > But I'm wondering: while you cite the Preetham paper you do use
> > different values for the A to C parameters and also for the Perez
> > formulation.
>
> I took the values that the Stellarium source code used rather than the
> paper itself, I guess the authors of Stellarium tweaked them a bit. I
> guess you can use whichever set look better for you.
>
> > Also I'm wondering about the multiplication factor of 1000 for the
> > zenith luminance. As far as I understand it this formula return the
> > luminance in cd/m2 therefore this additional multiplication just makes
> > the exposure factor unnecessary small.
>
> The formula in the paper gives the luminance in K cd/m2, that's why the
> 1000 factor is in there.

Quick question:

How do I convert the units of ExposureFactor to my scene?

In my scene, 20 units = 1 foot.

Thanks!!


Mike

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