Re: rodinal developer for infrared

[Kayo Matsushita <kayo@xxxxxxxxxxxxx>]

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 -



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Topic No. 16