Jul. 6th, 2005

mbarrick: (Default)
The replacement for the conductor ribbon I ripped in the course of removing the infra-red low-pass filter from my old camera arrived today. It was no big deal to replace and within minutes I had a fully-functional camera again. Then I went on to cobble this together:


And just what is this thing? Why, it is a slide holder containing a piece of exposed colour negative (black to the naked eye) duct-taped to a chunk of toilet paper tube, of course. And just why would I do such a thing?


Because the circumference of a toilet paper tube happens to be just the same as the barrel of the lens on my old camera, making it the perfect way to hold the black piece of exposed negative in front of the lens.

And what possible use is that?

Well, it turns out that exposed colour negatives may be black to the naked eye, but they are transparent to infra-red.

See the results )
mbarrick: (Default)
I should have thought of this earlier. The IR light coming through and the fact that my replacement for the IR-cut filter does not have the same visible tint was throwing the white balance off. I forgot the camera has a manual white balance control. Setting off a white piece paper I can wholly compensate for the magenta shift in colour in-camera:


IR+Visible, correctly white-balanced.



IR only, correctly white-balanced.

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