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04-22-2011, 12:32 AM   #1
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Which body for IR conversion?

I've decided to covert one of my surplus bodies to IR.

I have an *ist-D, *ist-DS, and a K10D that I could use for the conversion.

Which one would be best suited for IR?

Also, does anyone have any experience with the conversion done by Pro Camera in San Diego?

TIA

04-22-2011, 12:49 AM   #2
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I have a converted K10D from Spencer's Camera (830nm conversion). It's served me well. Just note that some of the more recent reviews for Spencer's are bad. Looks like I was one of the lucky ones. Here are a few from that camera.

Byodo-In Temple, Valley of the Temples, Oahu, Hawaii


Tunnel View, Yosemite National Park


Yaki Point, Grand Canyon National Park


Hakimo Road Ruins, Waianae, Oahu, Hawaii



I'm thinking about getting another K10D and going "full spectrum" rather than 830nm IR only. There are a bunch of other ones here.
04-22-2011, 01:49 AM   #3
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My suggestion: Get a conversion where the IR-blocking hot.filter is replaced with clear optical glass, NOT with an IR-pass filter. With an IR-pass filter built into the camera, you are limited to that spectral response, and you can never shoot non-IR again. With clear glass there, you have total control over spectra. You can mount 680-720-780-900-950-1000nm-whatever filters onto lenses for IR work, or mount an IR-block filter for 'normal' color work.

Yes, I know the trade-off: With clear glass inside the camera and filters mounted on lenses, you are limited to lenses that filt the filters. With an IR-pass filter in the camera, you can mount any lens. So I suppose the deciding factor is: Just how surplus IS the camera body? Do you want to dedicate it to 780nm or whatever work for the rest of its life?
04-22-2011, 02:37 AM   #4
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RioRico's advice is ok if your slr body has live view. If not, you still have the problem that you can see next to nothing through a lens-mounted filter.

04-22-2011, 03:51 AM   #5
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No matter where the filter is located in the optical chain, it still reduces visible light -- beyond 720nm, it's reduced down to blackness. Yes, LiveView is necessary for knowledgeable IR work. I mostly shoot IR on a Sony DSC-V1 with NightShot, where the internal hot.filter is pulled out of the optics path. Even with a 1000nm filter, its LiveView displays quite clearly. Shooting IR on ANY camera without LiveView is just shooting blind.
04-22-2011, 08:42 AM   #6
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I think you may have missed my point. If the IR filter is fitted on the sensor it makes the camera IR-only ( as you wrote ) for whatever wavelength you choose to have fitted. What it also does is place the filter in the taking path but out of the mirror/prism path behind the mirror. You see an unfiltered view through the viewfinder - not an IR filtered view - but at least you can see where you're aiming while the camera does the IR-filtered exposure. With liveview you can aim and gauge the effects of the lens-mounted filter by looking at the sensor output on the rear screen when you can't see through the viewfinder.

(Going for a lie down now)
05-06-2011, 02:29 PM   #7
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Hi, I bought a K110 and are using a 720 ir filter, haven't changed the camera and it works fine, but I can't se anything in the viewer, so have to gues what I gets on the picture. Autofocus is working ok. Convert the picture to black and white on PC.
Tried it on my K10D, but it didn't work.
Erik
05-06-2011, 03:34 PM   #8
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Pick the one with the highest resolution.

Note that after conversion, you have a sensor with 1/4 of original number of pixels (e.g. only 2.5 MP from a 10 MP camera).

Also, since exposure and AF are all messed up after the conversion, the ideal camera would have live view. AF with live view, through slow, is still correct after the conversion. But this does not apply because none of the cameras you list has live view.

05-07-2011, 12:47 AM   #9
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Two colors in the Infrared

QuoteOriginally posted by SOldBear Quote
....
Note that after conversion, you have a sensor with 1/4 of original number of pixels (e.g. only 2.5 MP from a 10 MP camera)....
I'm not sure what you mean. There can still be "color" in the IR. The Blue & Green filters act differently from the red filter at different light wavelengths. The blue & green filters are opaque in the near IR compared to the red giving rise to what are essentially two colors in the IR.

Here's an example of two colors in an IR photo:


The Sunglasses are blue because the Bayer Blue filter is pretty transparent in the longer (800+ nm) part of the IR spectrum The pink sky vs the white foliage is another example of IR color separation by the Red Portion.

I don't know how to exploit theses colors effectively but they are present if you use an filter that passes wavelengths shorter than about 800nm.

Here's a typical spectral transmission curve for a Bayer filter into the IR:
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