Re: rodinal developer for infrared

[bob.cassanova@xxxxxxxxxxxxxxx (Bob Cassanova)]

My experience with the Konica IR is as follows:     I meter with an
incident meter using ASA25 with NO filter in front of the meter.  I use a
#15 filter and open up 2 stops from the incident meter reading.   I develop
in D76 per the instructions with the film.     I've also observed that
opening up 3 stops with #25 is too much.    I don't use the #25 much but
would guess that opening up 2 stops from an incident measurement at ASA25
would be about right.      I've tried a #29 filter and opened up 4 stops
from the incident measurement at ASA 25 and have found that the negatives
are grossly over exposed.      The #15 filter with metering as described
above gives me the results I like.      Occasionally I will use a polarizer
plus the #15 and open up an additional 2 stops.


 Have you heard anything about the Konica IR film being available in Europe
in a 4X5 format?


>At 10:58 -0400 9/12/96, Russell J Rosener wrote:
>
>>What ASA did you use for the Konica souped in Rodinal? I've been getting
>>good results with ASA 100 and #25 red filter, but my develpoment times are
>>way longer than yours. Could also be the difference between meters. I
>>always use TTL for 35mm.
>
>I'm still trying to work out the best overall exposure setting for this
>film. I usually shoot at ASA 50 with #25 red filter or ASA 32 with #15
>filter, and bracket + and - 1 stop, using on-camera, through the lens (and
>filter) metering on my EOS 650. It would be interesting to shoot at ASA 100
>and try your development time to see what kind of result it yields compared
>to mine. You know, there are so many things I'd love to experiment with
>this film. But being a poor grad student, it's kinda tough to keep up with
>the cost. :<
>
>A couple of thoughts on exposure setting for Konica infrared...
>
>In "Infrared Photography Handbook", Laurie Anderson writes that both #25
>and #15 filters provide the same effect for Konica film due to its unique
>sensitivity curve quite different from that of Kodak HIE. Konica technical
>literature doesn't mention this, and I have no way of testing it
>critically. However, I shot several scenes (containing typical infrared
>rich elements) with both filters at ASA 32, and didn't see discernible
>difference aside from approx. 1 stop exposure gap between the two. I'd be
>interested to learn others' experience on this.
>
>Speaking of Laurie Anderson, she also writes the filter factor for infrared
>films differ from that of regular b/w films. According to the chart in the
>back of the book, #25 requires a compensation of 2 stops rather than 3, and
>for #15, 1-1/2 stops rather than 1-2/3 stops. Again, I don't know the
>reasoning behind this. But the exposure difference I got from the test
>seems to support it - the camera meter compensating for regular b/w film
>resulting in the big exposure difference between #25 and #15 filters on
>infrared film.
>
>Any thought, anyone?
>
>
>Kayo Matsushita - kayo@xxxxxxxxxxxxx -

Dr. Robert A. Cassanova
Director, GTRI Aerospace & Transportation Lab
Phone: (404)528-7826    FAX: (404)528-7019
EMAIL:    bob.cassanova@xxxxxxxxxxxxxxx



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Topic No. 24