Re: Does Humidity effect the exposure of HIE?

[George L Smyth <GLSmyth@xxxxxxx>]

ROLLAND ELLIOTT (Quality Assurance Co-Op) wrote:
> 
> My friend told me that humidity greatly effects the exposure of Kodak HIE.  He
> claims that high humidity air captures more infrared radiation and therefore ef
> fects the exposure.  I've never read or heard about this before.  Is there any
> truth to this claim?  If there is how would you compensate for it?
> 
> I personally don't think humidity would effect the exposure.  If anything, the
> longer wavelength of near infrared light would probably cut through water vapor
> and not effect one's picture.

There are six causes for variation in solar-radiation intensity: 1)
variations in the amount of heat radiation intensity at the surface of
the earth, 2) variations in the earth's solar distance, 3) amount of
water vapor in the atmosphere, 4) hazines of the atmosphere, 5) zenith
distance of the sun, and 6) altitude.  So yes, humidity does affect the
exposure.  OTOH, chances are good that you will not see a real
difference under "normal" circumstances.

george

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