On Wed, 31 May 2000 07:22:57 -0400, "Greg M. Johnson"
<gre### [at] my-dejanewscom> wrote:

>Does CCD mean a photograph of an actual object?

In this case, yes. For the record, "CCD" is an abreviation for "Charge
Coupled Device." CCD sensors are used in digital cameras. Cornell
University used a precision digital camera to photogragh an actual
box, "The Cornell Box", and used this as a reference for comparing
computer rendering systems. 

They also compensated for spectral response of the CCD sensor, the
spectral response of the camera lens, the spatial distortion of the
camera lens, polarization effects, and several other factors. They
also broke the visible spectrum into 76 seperate wavelength groups,
compared to POV-Ray, which only seperates light into the three groups
of Red Green and Blue. It would be *extremely* difficult for an
individual to make an exact replica of their testing system.

Still, I am considering constructing a simplified version of the
Cornell Box, or something similar. I'm thinking of building a physical
box, photographing it, and using that for radiosity comparisons. I'll
let eveyone know what sort of progress I achieve, if I actually go
ahead with the project. My main concern is making the project
something that another POV enthusiast could duplicate, unlike the
Cornell Box, which requires laboratory-grade equipment to deal with. 

Even though my tests would be much more crude than Cornell's, I think
they would still provide some insight for fellow raytracers. I
encourage anyone else interested in this sort of physical testing to
contact me through personal email or this news server.

By the way, which newsgroup should this project be posted in?

   povray.general  ?  
   povray.advanced-users ??

Later,
Glen Berry

( Remove the "7" from 7no### [at] ezwvcom to email me. )

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