Re: Contrast control for reversal


Judy Seigel (jseigel@panix.com)
Sun, 07 Mar 1999 04:41:58 -0500 (EST)


On Sun, 7 Mar 1999, Liam Lawless wrote:
> Initially I agreed with Sil that it wouldn't work, but thinking about it
> again it seems that he might be wrong because magenta light can be regarded
> as having a blue and a red component: a cyan filter will transmit the blue
> while holding back the red, whereas he seemed to be suggesting that a cyan
> filter would transmit no magenta light. I've contacted him offlist and am
> awaiting a reply.
>

Another possibility is that the theory doesn't apply. I had many an
airhead undergraduate who didn't know that variable contrast is a special
formulation & used to "correct" contrast of lith film with the VC
filters, until I explained, no you can't do that.

A few SWORE that it did so work, until I explained that that was just the
change in exposure, less exposure, less contrast. They either believed me
or pretended to. But now I'm thinking, it is possible that colored light
did do something to the contrast... a gray area, so to speak. Why not try
it, we'll never tell.

Judy



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