UNderwater Infrared Photography

I am one of those weirdos who like doing underwater B&W photography.

Normally I shoot neopan 1600, but I got to thinking what kodak HIE or

Maco 820 would look like if exposed underwater. Does anyone have any

experience with this? It seems like there is potential for some

striking images, but I really don't have a good ideo of just how much

IR light is even reaching me down there (say between 30 and 60 feet).

Does the water filter most of it out, or do you think it might work?

Also, if you've tried this, any reccomendations on how to rate the

film?

Should have mentioned I am also interested in the potential perils of focusing for IR film underwater.

I'm almost certain that water absorbs _all_ infrared radiation. That's why it comes out black with opaque filters. theo nly reason it's not completely black with a red 25 filter is because of visible light coming through.

 

allan

That's what I thought initially, but now I am not so sure.. If the the water isn't reflecting any of the light back at the lens, wouldn't it stand to reason that it is being transmitted through the water, and would be visable underneath?

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If the the water isn't reflecting any of the light back at the lens, wouldn't it stand to reason that it is being transmitted through the water, and would be visable underneath?</cite>

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No, by that logic, coal should be an excellent transmitter of visible

light, since it reflects so little light. But alas, just because a

substance doesn't reflect a certain wavelength well does NOT imply

that it must therefore transmit that wavelength. In fact, water

absorbs most infrared light, neither reflecting it nor transmitting

it.

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Actually, at 30-60 feet, not only is most infrared absorbed, but

almost all of the visible red light is also gone, giving a

strong bluish cast to the sunlight that filters down to that depth.

Is Konica's IR film still made? If so, this might be fun to try. IIRC, Konica's IR film isn't quite as "IR" as Kodak's and might be more useful underwater. Worth looking into?

IR only penetrates a few inches into the water. That's why it gets more blue the deeper you go. So two feet down, you're going to get an iso of say 6 with HIE. Just hope you can find something to mount your tripod on and tell any sealife to stay VERY still. But go on, have a go, and don't forget to post the results.

One consideration -- if you're set up to use an underwater flash, the output of a strobe has plenty of IR to rate your film as you would in sunlight. Of course, you'll then have to apply a filter factor for the water that varies according to distance -- like using a guide number with flash, only varying as the 4th power (or worse) of distance instead of the square, and having to apply the factor again for lens-to-subject.

 

With a ringlight and closeups, it could work...