Filters with Konica... need suggestions!

[WR <rivelli@xxxxxxxxxxxxxxxxxxx>]

Holly-

Slow down! You were on the right road originally; go back to where you
started, take a deep breath, and begin again.

1. The # 25 filter with Konica 750 gives very good results. Lighter filters
like orange # 22, yellow # 8 etc. also work, but give more subtle results.
That is, pale gray instead of white foliage, dark gray water instead of
black. The # 87, 89B and other IR filters are a problem because the film
has so little sensitivity in the region where they tranmit rays. They will
work, but you have to give even more exposure than with the # 25.

Stick with the # 25 until you have more experience with the film.

2.  Konica 750 and the Kodak films (HIE and HSI) are very different.
Sensitivity to different wavelengths, different contrast, different grain
structure.

For example, Konica has a recommended speed of ISO 32 (what you would set a
hand-held meter at; NOT necessarily where you would set a through-the-lens
meter --that's a whole other topic) when used without a filter. When using
the # 25 filter with Konica you have to give two stops more exposure,
making the film speed ISO 8.

The recommended speed of Kodak IR films is ISO 80 without a filter. Because
of the different sensitivity to red light compared to Konica 750, when you
use the # 25 filter with HIE/HSI you need to give only 2/3 of a stop more
exposure. And the tonalities and contrast of each film will be very
different.

3.  There should be NO "haze"! It's something else.

Put the camera on a tripod, make sure the lens and filters are reasonably
clean, have the sun at your back (it's not necessary to be up before
sunrise or wait until sundown), bracket your exposures +/- 1/2 stop and +/-
one stop,keep good notes, develop the film for the recommended time and
evaluate the negatives.

If they are "hazy", check your camera and darkroom for fogging from light
or IR. Put some film in your camera and take it out into the sun for a
while. Don't expose it. Develop it. Place a piece of unexposed film on the
counter in your darkroom for three minutes. Develop it. Both films should
be clear. (IR rays were going right through my darkroom door until I
discovered it).

4.  Take more pictures and keep notes. Your aim is to find a correct
exposure so that with only a +/- 1/2 stop bracket you can get consistently
good negatives. Check your exposure meter against some others; meters are
frequently off by as much as a stop.

Adjust the developing time so that you can get negatives which YOU can
print easily, to look the way that YOU want them to look. If necessary,
change to another developer and start again.

5.  There's nothing wrong with outdated film if it has been kept
refrigerated. Test a roll against a fresh roll to see if there is any
difference. Photograph the same subject and develop them the same. If the
outdated film is okay, buy a bunch and freeze it. I'm still using film that
"expired" years ago.

That should do it. Be methodical and consistent and KEEP GOOD NOTES and you
should have few problems.

Best Wishes,

William Rivelli         212 254-0990
303 Park Ave South      212 254-0922  FAX
New York, NY 10010

rivelli@xxxxxxxxxxxxxxxxxxx
    www.rivelli-william.com


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