Re: Infrared - black-and-white???

Father Kodak wrote:
On Tue, 02 May 2006 18:01:12 -0400, Dennis
<dennis@xxxxxxxxxxxxxxxxxxxx> wrote:


Used to use this a lot in the old days.

Kodak infrared Konica infrared
Agfa had a extended red ... I think


I froogled these films but got kits only for Kodak. And only for 35
mm single rolls. No long rolls or bulk load.

Try Gooling instead. My understanding is, Konica produced their IR film only once a year, in April, so supplies tended to be pretty limited, and I think they wrapped it up this year.

There's also a new import, called "Maco" or "Macophot", that is an extended range IR if I remember correctly.

Check out http://www.vividlight.com/Articles/2915.htm and http://www.apogeephoto.com/mag1-1/mag1-IR.html for a little more info. Also http://www.frugalphotographer.com/catMaco.htm

<snippage>

For my subjects it is not only what the object reflects, but what it
gives off because of internal combustion. At least that is the
intention.

Better put this one out of your head. IR films can only capture wavelengths existing just at the outside edges of visible light (for humans, anyway), what's often called "near infrared". Catching the wavelength given off by hot objects, "far infrared", requires very specialized equipment, expensive and bulky, not the least of which is due to the elaborate cooling system that must be used for the imager.

Most "IR" films hit at wavelengths overlapping visible light (that's the "extended range" - it's into visible, not further from it), and with a full-visible cutoff filter, you won't get much exposure. Kodak's HIE is the prime exception.

You can play around with IR with many digital cameras, quite easily. Some have IR filters in them, some don't, but most digital sensors have sensitivity beyond visible light. You can find out very easily, by aiming a TV remote at them and seeing if there's anything picked up by the sensor. With a realtime LCD display (i.e., not a DSLR), you can often see the light emitted by the remote at the time, and I even have it in a couple of pics - see http://www.pbase.com/shootin/image/48370152 , the point of light immediately inside the side mirror, which is my remote shutter release ;-)

A piece of unexposed, developed slide film works as a pretty good filter to cut nearly all visible light but lets IR pass, an old trick. Usually requires medium-format to be a large enough piece. Otherwise, research your filters carefully. Some let more visible light through than others, which may or may not be a wanted effect.

Good luck!

- Al.
.

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