Questions RE: Old, poorly stored film & B+W filter's IR Cmnt

[klycea@xxxxxxxxxxxxxxxxx (Adam-HALPID Klyce)]

     Ladies & Gentelmen,
     
     Hi'ya. I am planning a trip to Yosemite next weekend and as I
     started to pack some stuff last night I realized I have had a
     roll of Kodak's HIE in a photo-backpack for some time. It's 
     been in a closet but the temperature must fluctuate pretty
     much between 65 deg.(F.) & 70 deg.(F.) I am wondering if 
     any one else has had experience shooting HIE that has not been
     stored very well? I have many more rolls in the freezer and so
     I think for this trip, I would rather use something I am sure
     about than take chances with film that could be fogged.
     
     On a similar note, I have an unprocessed but exposed roll of 
     Ektachrome IR that I lost. I have found it and well, it's been
     sitting in my desk drawer for about 14 months. This, in a room
     that gets direct sunlight and fluctuates in temp. between 80
     degrees (F.) and 50 degrees (F.) Given the cost of developing
     this stuff, should I bother?
     
     Also, I happen to use B+W filters, and was looking in a brochure
     I have. For infrared they write:
     
     "In general, the sensitivity of black and white infrared film is
     about ISO 50/18-degrees. Kodak infrared film and the B+W filter
     #092 is about ISO 20/14-degree; with the B+W filter #093 about
     ISO10/11-degrees. However, these values are highly dependent on
     the strength of the infrared radiation in the scene which is 
     much higher when the sun is low than at any other sun angles...
     
     ...The impressive special "wood-effect" (very bright to white
     reproduction of chlorophyll in black and white positive images)
     appears the strongest at low sun angles. Under such conditions, 
     a strong red filter plus normal black and white film is 
     sufficient. Infrared pictures without filters always produce
     unsatisfactory results similar to black and white pictures 
     missing tonal value graduation and color pictures showing a 
     strong blue-green tint and little color differentiation."
     
     (Now, aside from the rather subjective tone of the peice (though
     rather appropriate for a company that makes & sells filters) I
     wonder; has anyone else noticed a shift in the strength of IR
     at Dawn & Dusk? Is this a clue in the mystery of trying to find
     a general approach for metering for IR film?)
     
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     B+W Filter #092 - (Schott RG 695) - Dark Red which filters out
     light below approx. 650nm. Filter Factor approx. 20-40.
     
     B+W Filter #093 - (Schott RG 830) - Black which filters out
     the entire visible spectrum, or below 1000nm. 
     
     B+W Filter # 094 - (Schott RG 1000) - This filter transmits the
     invisible long-wave radiation in the spectral range above 1000
     nm virtually unweakened. A pure infrared picture is the result.
     
     B+W Filter # 099 - (Schott OG 530) - Orange, blocks the blue &
     blue-green portion of the visible spectrum up to approx. 500nm.
     
     
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     
     Hope some of that was of interest. I do not work for, or know 
     anyone who works for, B+W or Schneider Kreuznach and this does
     not constitute an endoresment.
     
     -Adam.
     

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Topic No. 5