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Re: Green Light



Malcolm Todd wrote:
  
> > The only requirement that matters is that the complete path is accurately matched, and that the detectors have the dynamic range and sensitivity to capture accurately minute changes in light level.

Yes, light level. But we are not talking B/W film here are we? If you
shoot with a green filter on the camera you'll have a difficult time
sorting out what was red and blue in the scene. After splitting the
color channels into 3 x B/W on material transfered on both Ursa and
Spirit we see that the noise in the blue channel is SIGNIFICANTLY worse
on the Ursa material. Croma keys are a lot nicer (end easier) on Spirit
material. My guess is that the CRT light contains little blue and that
it has to be amplified a lot to get a result that "sort of represents"
the original neg. 

As far as I know, to do a correct spectral analysis you have to start
out with a light source that contains all the wavelenghts (or as close
as possible) you want to analyze. In the case of film white would be the
right starting point.

In the case of going back to film and matching to orig. neg. shots it's
my believe the CRT's will have a hard time. The best known technology
today in order to get close to a representation of film is CCD's. Either
using 1 pass for each color or beam splitting onto 3 chips. I believe
the first method is used in the Cintel Klone in order to capture the
neg. as correctly as possible.

Best regards

Kris, Destiny-601 & The Warehouse.

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