Splotches on Infrared 5x4 film

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Hi All,

I have a fair amount of experience shooting Kodak HIE in 135 format, as well as processing 135 B&W film, and normal B&W 5x4 negatives. Recently I tried to shoot a couple of infrared shots in 5x4 and ran into a problem.

I was shooting with a wooden holder with a metal slide, which is (visible) light tight, processed in Aculux 2 for recommended time (15min @ 20 degrees for G0.7 density). Agitation was standard, tray processed.

The outcome was that half the neg, corresponding generally to the scene, was filled with out of focus dark and light splotches, over the areas where there were leafless trees. The denser parts of the neg that were the sky and a cathedral seem to be unaffected by these splotches.

I have asked around and haven't found anything conclusive. And help as to why this happened would be greatly appreciated!

-- Jed Wee (jed@essence-of-light.com), March 27, 2001

Answers

Sample image:

http://203.120.80.249/forum/messages/35/7322.html?FridayMarch232001025%206am



-- Jed (jed@essence-of-light.com), March 27, 2001.


It really looks like your holders may be the problem. Try plastic ones. It looks like the UV is filtering through the holders which aren't perfect in evenness as far as the darkslide goes. Just a thought. You might have tiny pinholes in your bellows also. It won't take much to fog this film as you know.

-- Scott Walton (f64sw@hotmail.com), March 28, 2001.

Thanks... I'm going to try another few frames through a new Fidelity holder when I get the chance. Generally, my 5x4 trannies are fine so if there is a leak, it's got to be an IR thing... but the lighter splotches don't seem to me to indicate a leak, which is baffling.

-- Jed (jed@essence-of-light.com), March 28, 2001.

I suspect something other than light leaks, since the affected areas are lighter, not darker. It looks more like some sort of chemical fog. Is that reticulation in the upper left corner?

-- Ed Buffaloe (edb@unblinkingeye.com), March 29, 2001.

Having processed a ton of 4x5 ir sheet film using every method known to man, I'd say this is definately a processing problem. Did you use gloves to load this film? Left upper corner looks like finger smudges. Are you sure you used the correct processing techniques for tray development? This looks like bad agitation technique. If the problem was shooting through leafless tree branches the image would have been much more discreet. IR has a tendency to lightpipe when a lot of elements like leaves and branches are in the way. But they are usually defined much better. I'd opt for some other processing method with IR sheets. Let us know your next outcome. James

-- james (james_mickelson@hotmail.com), March 31, 2001.


Hi guys,

Thanks again... no, that bright spot on the top left hand corner is just a reflection from the neg from some lazy copying for posting on the web with a digital camera...

I've posted this question on photo.net with differing replies as well. Someone quite confidently assured me this was a film holder problem... so it seems I'm a bit stuck and will have to figure this out the old fashioned way. I'll have a go and see what happens.

-- Jed (jed@essence-of-light.com), March 31, 2001.


If it was a holder problem it would be uniform. IR is very sensitive to light and it wouldn't be splotchy it would be completely white(or black on the neg). When IR isn't processed correctly it gets this mottled appearance. It looks suspiciously like improper agitation. Or possibly chemical fogging but that would also be uniform. james

-- james (james_mickelson@hotmail.com), April 01, 2001.

Hi All,

Update (Problem solved)

I've just processed another pair of infrared negs of the same scene, this time without any problem.

The only two things I did were agitation and film holder. Agitation -- just took a bit more care this time, though I don't think I was being particularly sloppy the last time. I used an almost new Fidelity holder (used twice previously by myself), with plastic frame and plastic slide. I am of the opinion that it was indeed the pressure plate on my first holder that caused the problem, as I can just about make out imperfections when held obliquely to the light.

Thanks for the suggestions, all!

-- Jed (jed@essence-of-light.com), April 04, 2001.


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