Hexar AF for IR

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I have a Titanium AF and recently received some EFKE IR film. I figure that since this model is reputed to recognize Kodak and Konica IR films, I might do well to choose one of those settings.

However, despite some internet searching, I have not come up with the method. Any ideas?

 

[Moriturii]

Infrared auto focus

• load film, and switch camera on (P, A, or M mode)

• IR film is non DX, so requires pressing the shutter release button to advance to frame 1.

• switch to A mode, then press SELECT until ISO values are displayed. Within 3 secs, press DOWN untill [---] is shown. press MF once to display [750] (corresponding to Konica IR750 film) press MF twice to display [850] (corresponding to Kodak's 850 film) (the numbers correspond to the wavelength the films are sensitive for)

• after 3 secs, the display will show [iso 100], acknowledging successful setting of IR value.

• for correct exposure, consult the data sheet of the film.

 

[flip]

Go figure. It doesn't appear to work with my Hexar. It goes down to ISO 6 and just stays there. Hrmmm.

 

[Moriturii]

http://www.rangefinderforum.com/forums/showpost.php?p=864265&postcount=15

I'm so lazy, I am just copy pasta thing left and right. Does this work?

 

[shiro_kuro]

Infrared auto focus
load film, and switch camera on (P, A, or M mode)
IR film is non DX, so requires pressing the shutter release button to advance to frame 1.
switch to A mode, then press SELECT until ISO values are displayed. Within 3 secs, press DOWN untill [---] is shown. press MF once to display [750] (corresponding to Konica IR750 film) press MF twice to display [850] (corresponding to Kodak's 850 film) (the numbers correspond to the wavelength the films are sensitive for)
after 3 secs, the display will show [iso 100], acknowledging successful setting of IR value.
for correct exposure, consult the data sheet of the film.


The Ultimate Hexar AF Thread

 

[flip]

Yay! Film in the chamber and I'm in business. Thanks!
It's set for 850, which appears to be the closest to 820. 🙂
The freestyle photo page reads:

Note: Testing of this emulsion has shown that the best results are obtained by using an Opaque Hoya R72, Tiffen #87, #89 or B+W 092 filter and rate at 1 - 1.5 ISO. Aperture f/16 - 1 - 8 second exposure. (Reciprocity failure applies)

Near-infrared results are obtained by exposing the film at ISO 25 with Red 25A filter. Aperture f/16 Shutter speed 1/30th second.

I'll use the R72.

Aside from completely manually guestimating times or using another meter, I wonder if there is any way to automate the metering for this situation. It appears that if I set the ISO to 6 and exposure compensation to +2, I could be around 1.5 ISO. BUT, I am not sure if resetting the ISO clears the setting for 850 IR film focussing.

Sorry for all the questions. I just want to do the legwork before I shoot rather than track down problems afterwards.

Cheers,
Phil

 

[flip]

Found some information.

http://www.apug.org/forums/forum37/78808-efke-4x5-infrared-820-aura-film-first-try-3.html

There is a loose correlation between conventional meter readings and infrared exposures. My Pentax spot meter was set at EI=1.5 for sunlit scenes, EI=0.75 for sunny day subjects where shadow detail was important, EI=0.3 for cloudy overcast days. Exposures were through IR680 and IR720 filters. Surprisingly it did not matter which filter was used. The results looked much the same!

Efke IR 820 film shows significant reciprocity failure but the following corrections worked well:
1 second metered, give1.5 seconds
2 seconds metered, give 3.5 seconds
4 seconds metered, give 8 seconds
8 seconds metered, give 24 seconds
15 seconds metered, give 1 minute
30 seconds metered, give 3 minutes
more then 30 secs, give up.

i will assume that the benefit of accurate focussing in IR on the AF comes at the cost of some flexibility. So, it will be a M-setting affair in IR with this film.