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  1. #21
    keithwms's Avatar
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    Quote Originally Posted by Nikanon View Post
    Color infrared is impossible with black and white film, there are no dye couplers in the emulsion to record individual colors, simply the silver halides (plus sensitizers) reacting with photons. Recording black and white film with different color filters will only give you different tonal relationships, but not record any color information.
    As mentioned: not only will it work, it'll work well. A lot of colour work was done with b&w film. The idea of colour sep goes waaay back. In my own research on the topic, I quickly ran into James Clerk Maxwell; yes, the Maxwell of del dot B equals zero fame. That was around the 1860!!! Apparently Maxwell was the first to propose colour sep for capturing and displaying colour images. Nobody was thinking of multilayer colour film at the time, much less colour roll film or c41 or e6 or whatever.

    Doing IR colour sep will be easy. The interesting wrinkle is what colour channel you dump the IR info into; IR is, of course, invisible to us and doesn't have a colour. So it is a matter of choice. For spy photos you'd probably want the IR to be something other than red so that it stands out from that adjacent colour. But for more pleasing images I suspect that putting the IR image into the red or deep red channel of the final image will work. People can simply try and see for themselves... many creative possibilities here.

    Of course, the individual b&w images could also be developed as positives, they don't have to be developed as negs.

    Smart chemists like Ron could tell us how to make IR autochromes.

    As certain film options go off the market, we'll simply rediscover all the ingenious things that people used to do. It'll be fun, it really will.
    "Only dead fish follow the stream"

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  2. #22
    holmburgers's Avatar
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    Quote Originally Posted by keithwms View Post
    As mentioned: not only will it work, it'll work well....

    ...As certain film options go off the market, we'll simply rediscover all the ingenious things that people used to do. It'll be fun, it really will.
    Touche!!

    Stephen Frizza's example there is an awesome one.

    The comment about static subjects could be rememedied with a one-shot camera...
    http://www.apug.org/forums/forum127/...resources.html

    Dye-transfer is definitely not the only way to do this and as has been discussed, is a difficult process to "jump into" due to the lack of supplies readily available. Tri-color carbon would probably be a better option, carbro, etc. Not to mention tri-color gum bichromate. Or, one could tone the separations individually with chemical and/or dye-toning to achieve loose seps that could be registered for the sake of display/scanning/printing.

    http://www.apug.org/forums/forum37/8...or-toning.html

    Lastly, I'd like to know more on the last comment about IR screen-plate (autochromes) photographs. I actually had this same idea but can't quite reason how it could be done. The screen would have to go thru a registration shift, since the encoding filter would have to be opaque and the viewing filer would have to be red....... [... another day i s'pose]
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  3. #23
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    Quote Originally Posted by Stephen Frizza View Post
    This image was done via the technique mentioned above. This portrait of me was made by APUG member Goldie.
    Something definitely Christopher Walken-ish about those eyes...
    hmmm...that explains a lot!
    I do use a digital device in my photographic pursuits when necessary.
    When someone rags on me for using film, I use a middle digit, upraised.

  4. #24
    holmburgers's Avatar
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    Quote Originally Posted by happyjam64 View Post
    Edit: Does anyone know the spectral sensitivity of the infrared layer in EIR? Or what that layer actually captured?
    http://www.kodak.com/global/en/profe...323/ti2323.pdf

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  5. #25

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    Ah-ha, thanks holmgurgers, that was exactly what I was looking for! Now, what infrared film is closest to the curve of the cyan layer...

  6. #26
    keithwms's Avatar
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    Quote Originally Posted by happyjam64 View Post
    Ah-ha, thanks holmgurgers, that was exactly what I was looking for! Now, what infrared film is closest to the curve of the cyan layer...
    I would go with Rollei Superpan and use an rm72 filter or a #87 if the subject permits long exposures. I have also had excellent success with Rollei IR.

    I have had decent success with the Efke IR films but I have also had spurious quality control issues. The Efke IR probably has the deepest IR sensitivity on the market right now, and if you like halation they have the version without the AH layer.

    One slight mark against the Efke for colour sep work (which will require several good negatives) is that it scratches more easily than the Rollei. Of course, you could simply be more careful with it...

    For me though, superpan is tops.
    "Only dead fish follow the stream"

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  7. #27

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    Hmm, thanks for the suggestions! I think I'll probably go for the Rollei IR in 4x5 and bi-pack it with ortho film. I can't wait to see what comes out!

    Edit: Just had another thought. What if we used infrared imagesetting film? As far as I know, imagesetting film has a much narrower band of sensitivity. The only problem is that imagesetting film is naturally high contrast, but I'm sure it could be toned down with the right developer combination.
    Last edited by happyjam64; 09-06-2010 at 06:02 PM. Click to view previous post history.

  8. #28
    keithwms's Avatar
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    I don't know anything about the spectral sensitivity of imagesetting film. Anyway, you probably want to use a film that can handle the blue, green, red and IR separations equally well. Then you just swap out filters and shoot the different frames in series on the same roll of film, develop them all together...
    "Only dead fish follow the stream"

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  9. #29

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    Haha, that would be a lot easier! Now I just need to order some wratten filters...

  10. #30
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    happyjapm64, although I think it's a cool idea I'm not sure if this bipack method will work.

    First, how do you intend to match the speeds of the two films? Is there an ortho film that is slow enough and a IR film that is fast enough to make for the same exposure times w/ this bipack? The IR has to go thru the ortho film and a red filter, meanwhile the ortho film is right on top w/ no filtration.

    And also, since the ortho would be, as you said, a record of the green & blue, it's not a true color separation by any means. Same goes for the IR layer which thru only a red filter won't be 100% IR.

    So false color it surely will be, but Color EIR it certainly can't resemble (why am I talking like Yoda?). That being said though, it could still be very interesting.

    The best method would be a one-shot camera (not practical... prohibitively expensive IMO) or just using filters and taking three individual shots. However, I do like the idea of bi/tri-packing it, but the particulars need to be ironed out.
    If you are the big tree, we are the small axe



 

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