First time IR820 use. Some confirmation please.

Discussion in 'Exposure Discussion' started by Craig Swensson, Mar 5, 2011.

  1. Craig Swensson

    Craig Swensson Member

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    I am asking for a little confirmation here.I have done some research around the threads here and looked at other info also. Seems that all the info combined can make the process seem a little `muddled'. I understand that the use of IR film requires experimentation and bracketing so i`m really just after a starting point. Here is what i plan to do.

    1.Developing in Microphen so i will set ASA @ 200[i`m not sure on this]
    2.Use an SLR over the rangefinder because i really do not fancy loading an FSU in complete darkness. A rangefinder would be preferable but i have an external 35/85 veiwfinder i could use on the SLR.
    3.Take photos a couple of hours after noon on a bright day.
    4.Assuming an exposure without filter of F16/125 i will add a filter factor of 5 for a 720nm filter.[obviously use tripod]
    5.Fit filter after taking reading and not look through the veiwfinder with the IR filter attached.
    6.Bracket each side of filter factor exposure.
    7.Should i develop in stock solution or 1+1?

    What have missed/got wrong? And any tips
    regards
    CW
     
  2. 2F/2F

    2F/2F Member

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    Hi,

    Don't forget to shift focus.

    The film's speed is ISO 100 unfiltered.

    I would just use EI 1.5 on a clear sunny day, forget the meter, and use sunny 16 as a guideline (1/2 sec at f/16, f/2 at '125, or any other equivalent exposure). Cloudy days, overcast skies, shade, etc. will require much more exposure.

    Again, don't forget to shift focus!

    Oh yeah, and I know it is stating the obvious at EI 1.5, but bring a tripod!
     
  3. DWThomas

    DWThomas Subscriber

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    I concur with 2F/2F. And when you say "add a filter factor of 5 for a 720nm filter" I hope you mean 5 stops; even then, I would assume 6 stops for a starting point based on recent experience. I used an SLR myself (Bronica SQ-A) but popping filters on and off is a pain. I may go with my Yashica 124G on the next pass (didn't have it when I started on the IR stuff).
     
  4. Craig Swensson

    Craig Swensson Member

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    2F2/F,thanks. yes i forgot to add focus shift to my basic list but was aware. unless i use 35mm lens or less.

    DW, yep, i meant 5 stops,[ now 6. thanks]

    and am i correct in assuming that if I dial in exposure compensation to
    + 2 i can then use EI 3-4?
    cheers
    CW
     
  5. MattKing

    MattKing Subscriber

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    IMHO, a handheld incident meter is a much more appropriate tool for metering when you shoot near IR film.
     
  6. Craig Swensson

    Craig Swensson Member

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    Well the starting point of F16 @ 1/2 sec worked out OK, a couple of prints acceptable and a few negatives that could be worked on. I used the handheld in combination with exposure compensation as my meter only goes to EV6.A lot of note taking done and much experimentation to go.
    regards