Rollei IR 400 in mixed light with IR flash

Discussion in 'Alternative Processes' started by Harry Lime, Mar 29, 2012.

  1. Harry Lime

    Harry Lime Member

    Messages:
    476
    Joined:
    Dec 10, 2005
    Shooter:
    35mm RF
    I'm shooting an extended project that will include some concert photography. The venue forbids flash photography during the show, which presents something of a problem. Light levels will be low and I don't want to have to switch to digital for this section of the project.

    So, I thought about shooting Rollei IR 400 with an IR flash. I am not looking for the IR look, so I will not use an IR filter on the camera lens.

    Instead I am aiming for the IR filtered flash to act as an invisible IR fill light that will be picked up by the extra IR sensitivity of the film.

    So, essentially I will shoot:

    - Mixed light
    - No IR filter on lens
    - Heavy duty IR emitting flash (on camera)
    - Rate Rollei IR 400 @ 400

    Also does anyone have any experience pushing Rollei IR 400 to 800 or 1250?

    I'm going to run a few tests in advance, but would like to hear from anyone who has experience with this.


    Thanks in advance.
     
    Last edited by a moderator: Mar 29, 2012
  2. djhopscotch

    djhopscotch Member

    Messages:
    148
    Joined:
    Aug 29, 2007
    Location:
    San Jose, CA
    Shooter:
    4x5 Format
    Would tge focus shift present a problem when mixed with the visible light to expose the image?

    Sent using Tapatalk
     
  3. DWThomas

    DWThomas Subscriber

    Messages:
    2,898
    Joined:
    Jun 13, 2006
    Location:
    SE Pennsylvania
    Shooter:
    Multi Format
    My guess is it might offer some help, but perhaps not much. I doubt focus shift would be much of a problem, as the Rollei material doesn't extend very far into the IR range. That same limited IR range could mean you won't get much fill, as in daylight the film requires about six stops additional exposure with a 720 nm IR filter which passes the near IR range barely outside the visible wavelength (but I guess there's one way to find out. :D)

    Could be fun to try. What will you use for an IR flash?
     
  4. keithwms

    keithwms Member

    Messages:
    6,074
    Joined:
    Oct 14, 2006
    Location:
    Charlottesvi
    Shooter:
    Multi Format
    It's an interesting idea. I am a bit doubtful that you'll get much boost for the IR flash, though. What's it output spectrum? if you put an rm72 over the light source, I doubt you'll get much extra exposure of the film. It'll just have to be tried.

    This film has rather limited IR sensitivity. A very deep red flash should be much more effective and not too intrusive. But bear in mind that you probably lose 3 stops of flash power when you gel it.

    The reason why the IR flash strategy works well with digital is that the digital sensors are very IR sensitive, so much so that it is a problem. Alas the Rollei film and superpan and the Efke and Ilford films aren't nearly as IR sensitive.
     
  5. EASmithV

    EASmithV Member

    Messages:
    1,925
    Joined:
    Aug 22, 2008
    Location:
    Maryland
    Shooter:
    Multi Format
    Weegee did a similar technique with black painted flash bulbs and IR film. Might try using flashbulbs?
     
  6. keithwms

    keithwms Member

    Messages:
    6,074
    Joined:
    Oct 14, 2006
    Location:
    Charlottesvi
    Shooter:
    Multi Format
    Just remember that Weegee was "in your face" most of the time. For most concerts, that isn't the case.
     
  7. DWThomas

    DWThomas Subscriber

    Messages:
    2,898
    Joined:
    Jun 13, 2006
    Location:
    SE Pennsylvania
    Shooter:
    Multi Format
    On further thought, back in the Bronze Age, ca. 1958 or so, a friend of mine attempted to rig up an IR flash using a kit built electronic flash that was a bit of a monster and the IR filter from some WWII/Korea night vision gear. The filter was about the size of the filters for Kodak bullet style safelights. Even though you couldn't see through it, there was a quite visible deep red glow when the flash fired. It was orders of magnitude less disturbing than an open 120 ws flash, but it wasn't exactly 'stealth." Not sure he ever did anything with it but the experiment itself.

    (And I dunno, IR works with the dig!t@l stuff if it's designed for it, or has had the IR cutoff filter removed. But with a 760 nm filter, my EOS40D needed many seconds of exposure in bright daylight to catch anything. I don't follow it closely, but AFAIK, the fundamental sensor elements pick up IR readily, but the package includes filtration to seriously attenuate the IR.)
     
  8. Harry Lime

    Harry Lime Member

    Messages:
    476
    Joined:
    Dec 10, 2005
    Shooter:
    35mm RF


    I'll match the IR filer on the flash to the spectral sensitivity of the film.
    Unfortunately ROLLEI IR seesm to only go as far as 820nm. KODAK HIE went well over 900nm...
     
  9. Harry Lime

    Harry Lime Member

    Messages:
    476
    Joined:
    Dec 10, 2005
    Shooter:
    35mm RF
  10. keithwms

    keithwms Member

    Messages:
    6,074
    Joined:
    Oct 14, 2006
    Location:
    Charlottesvi
    Shooter:
    Multi Format

    Yes, the Rollei (and similar) film only pokes a bit past the visible red. To get "true" IR effects I find that deep filters and rather large exposure compensations are needed with this film.

    Let me suggest superpan and a deep red gel over the flash.
     
  11. lowlight

    lowlight Member

    Messages:
    2
    Joined:
    Apr 8, 2012
    Shooter:
    35mm
    Harry Lime, I would be keen to know how your experiment goes with the IR flash. I am improvising a similar system using a Nikon EM camera set on the manual shutter speed of 1/90. Mounted on this is a Vivitar 283 flash unit covered with a 720nm filter. This will be for photographing wildlife at night at some distance. I will have to do a test run when I have adapted the flash unit. I did try Efke IR820 film with a 760nm filter (on a weaker flash unit than the 283) and I captured virtually nothing. I think this was because the Efke is a slow film, even if it is more receptive to IR at a higher frequency. I am hoping the faster Rollei film might produce better results.
     
  12. keithwms

    keithwms Member

    Messages:
    6,074
    Joined:
    Oct 14, 2006
    Location:
    Charlottesvi
    Shooter:
    Multi Format
    Lowlight, the Rollei isn't really much faster than the Efke.

    The issue is the spectral sensitivity of these films. If you look at the curves, the sensitivity drops off very rapidly in the near IR.

    http://www.digitaltruth.com/products/product_tests/infrared_film_010.php

    To play the IR flash game, you really would want some fresh HIE or... a (sorry, sorry) digital camera with the hot mirror removed:

    http://www.maxmax.com/camera_technical.htm

    I have one of these unmentionables and can actually make IR movies of it with a deep IR filter. I do wish HIE were still around....

    N.b. it may be possible to boost the IR sensitivity of the Efke or Rollei by treating it with some sensitizer or by hypering it. Ron could advise.
     
    Last edited by a moderator: Apr 8, 2012
  13. georg16nik

    georg16nik Member

    Messages:
    1,044
    Joined:
    Aug 3, 2010
    Shooter:
    Multi Format
    You need IR illuminator, not IR flash.
     
  14. lowlight

    lowlight Member

    Messages:
    2
    Joined:
    Apr 8, 2012
    Shooter:
    35mm
    Thanks keithwms and georg16nik. I would really like HIE to still be around too. You see it on ebay now and again, but course expired. You can even buy old Kodak Aerochrome 1443 on ebay but not sure how far into IR realm that film goes. I have a good IR illuminator to boost the range on my Sony nightshot camcorder, but I definitely want to try IR flash with film. I did consider breaking open my Finepix S6500fd and removing the hot mirror but would probably wreck it if I tried, or fail to put it back together properly. I don't want to pay much, so ideally want to use the 35mm film photographic equipment I already have. Using a 720nm filter on a powerful flash unit like the Vivitar 283 should give me a window of some 40nm in spectral sensitivity (720nm filter with film sensitive up to approx 760nm=40nm). It's not a big margin to play with but theoretically it should produce something the film can capture. Still, I'm tempted to buy the next decent looking roll of HIE that comes up on ebay.
     
  15. georg16nik

    georg16nik Member

    Messages:
    1,044
    Joined:
    Aug 3, 2010
    Shooter:
    Multi Format
    surveillance specs IR illuminators goes up to 950nm, usually have an optional image intensifier tube, could lit quarter mile distances with ease.
    Zeiss used to manufacture such toys and these days could be found second hand for reasonable prices.
    Films like Rollei ir400 (Agfa) or Efke ir820 were designed around such IR illuminators