This is something I posted to Digital Photography Review, but I thought it might find a place here. As per an earlier thread, I have bought a Kodak DCS 460. It is sensitive to infra-red, which tends to make the photographs look as if they have been stained with blood. Foliage in particular comes out a horrible dead-looking grey/green. I was unwilling to buy a 77mm hot mirror filter for my wideangle lens, because such filters cost £100+, but a quick look on eBay revealed that much smaller hot mirror filters are available more cheaply. At first I thought about buying a square filter and simply taping it to the front of the sensor - ignoring the possibility that the filter simply might not work unless it is outside the imaging pathway - but there doesn't seem to be enough space between the sensor and the shutter for this. Instead, I have taken a leaf out of Kodak's later DCS cameras, and I have mounted the filter between the lens and the shutter, thusly:
Obviously this is not work of a professional standard, and there is always the danger that it might fall off, and destroy the shutter. Nonetheless I was surprised to find that the results are generally good. Not perfect, but much much better than before, to whit:
Reflections tend to have a reddish tint, perhaps because the filter only reflects or blocks infrared radiation of a certain polarity. I literally made that up, I don't know. The second photo still has a reddish tint, but it's not offensive and would probably go away if I properly colour balanced the image. But I'm impressed with the results from a camera that dates from 1995.
Early DCS infrared hack
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Re: Early DCS infrared hack
Neat trick. Thanks for sharing!
(I agree there's a certain risk that the filter can come loose and destroy the mirror, shutter, or something. Be careful.)
Jarle
(I agree there's a certain risk that the filter can come loose and destroy the mirror, shutter, or something. Be careful.)
Jarle
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Re: Early DCS infrared hack
Hi,
I think your reddish tint on reflections is a result of the IR filter having a slight tilt to it in its mounting. It's tough to get it mounted such that it's exactly parallel to the imager when you're in the DIY mode there!
Later!
Stan
I think your reddish tint on reflections is a result of the IR filter having a slight tilt to it in its mounting. It's tough to get it mounted such that it's exactly parallel to the imager when you're in the DIY mode there!
Later!
Stan
Amateur Photographer
Professional Electronics Development Engineer
Professional Electronics Development Engineer
Re: Early DCS infrared hack
I've found that the hot mirror makes a huge difference (but at times, I like to take it off).