loading IR in the light? use a tent?

DaveOttawa · Sep 24, 2007

winger said:
Maybe I was lucky?

Yes, fridge probably helped too.

A thought: earlier on in thsi thread the lack of anti-halation layer on HIE was mentioned, maybe that IS a factor in causing pinholes. Not through any optical effect but because the emulsion is in contact with the uncoated film base (Estar I think in this case) rather than an antihalation layer as in typical panchromatic films. The exact mechanism I could not guess at (even though this the internet...) but but maybe it is a factor.

keithwms · Sep 24, 2007

I think it's probably a combination of the low-energy sensitization of the film and the static issues that make HIE more susceptible to cosmic ray damage.

In the past when loading IR films (not HIE but another one) I actually saw static flashes in the dark! Uh oh! This is perhaps relevant because ionizing cosmic radiation will probably be more likely to seed defects in a more staticky film.

Also, in school, I recall seeing pinholes in film taken up in a weather balloon, and this was attributed to ionizing radiation. I can't find an example online, that kind of demonstration precedes the internet; nowadays people take up solid state detectors. But I guess NASA still uses silver halide film for dosimetry:

http://spaceflight.nasa.gov/shuttle/reference/shutref/crew/radiation.html

Perhaps an antistatic and/or antifogging prewash might help. Any high-altitude recon guys or gals on here? They must have faced this issue at high altitude when using IR film.

eddie gunks · Sep 24, 2007

thanks guys. i will spring for another roll from my local rip-off-shop (read $15/roll) to test to put myself at easy. my friends/clients really want IR shots so i do not want to F it up on something as simple as old film.

as you can see the images were from SE Asia and an airplanme was used to get there....and it was hot theree.....and....and ...and

thanks for all the help. i will post again as i learn from my tset tomorrow and i will post again after Sat. wedding.

cheers

eddie

DaveOttawa · Sep 24, 2007

keithwms said:
I think it's probably a combination of the low-energy sensitization of the film and the static issues that make HIE more susceptible to cosmic ray damage.

In the past when loading IR films (not HIE but another one) I actually saw static flashes in the dark! Uh oh! This is perhaps relevant because ionizing cosmic radiation will probably be more likely to seed defects in a more staticky film.

Also, in school, I recall seeing pinholes in film taken up in a weather balloon, and this was attributed to ionizing radiation. I can't find an example online, that kind of demonstration precedes the internet; nowadays people take up solid state detectors. But I guess NASA still uses silver halide film for dosimetry:

http://spaceflight.nasa.gov/shuttle/reference/shutref/crew/radiation.html

Perhaps an antistatic and/or antifogging prewash might help. Any high-altitude recon guys or gals on here? They must have faced this issue at high altitude when using IR film.

Sorry old bean but none of the above seems to apply at all to the OP's stated and shown (see scans) problem. He is observing black spots on prints/white spots (holes, lack of density) on the neg emulsion, you are talking about various effects which would lead to extra density on the neg.

Cor · Sep 25, 2007

I have used quite few rolls of outdated HIE, and never observed this problem. I do store my film in the freezer (-20degC).

It has been reported in the past that the sheetfilm version (HSI) was plagued with pinholes (as can be seen in the photograph of above link), it was rumored that that was one of the reasons Kodak quited making this film (another was the declining sales to the army), and it indeed resembles the problkems of the OP

Best,

Cor

Chris Usher · Sep 26, 2007

IR black spots on negs

eddie gunks said:
thanks so far. the spots show up more on certain frames. maybe the pressure plate is to blame. i am shooting HIE 35mm. what could i use on my pressure plate? now i am beginning to worry about solving this problem. i never thought about the pressure plate! damn! i am shooting an N90S.

eddie

I read recently (can't remember where) that there can be a problem with air bubbles during development. The remedy is to pre-wash with water or bang the heck out of the developing tank after adding the developer.

DaveOttawa · Sep 26, 2007

Maybe, maybe not

Chris Usher said:
I read recently (can't remember where) that there can be a problem with air bubbles during development. The remedy is to pre-wash with water or bang the heck out of the developing tank after adding the developer.

I've heard this one too and decided to test it: Tried a pre-soak w Photoflo, made no difference whatsoever (still got the same pinholes).

I always firmly tap the tank during the first couple of agitations when developing (including those rolls which showed pinholes).

It hasn't come up in this thread yet but in case it does I tried using a water stop bath instead of acid, again, made no difference whatsoever (using D76, which, Kodak told me, contains no carbonate to make CO2 gas with acid to make pinholes).

eddie gunks · Sep 26, 2007

thanks guys! it looks to have been the film. a shot from my tset roll.

eddie

DaveOttawa · Sep 27, 2007

eddie gunks said:
thanks guys! it looks to have been the film. a shot from my tset roll.

eddie

So I take it this was non-expired ilm, cold stored until exposure and processed shortly after exposure?
Good luck with the wedding shoot, hope everyone likes the IR work.

keithwms · Sep 27, 2007

DaveOttawa said:
Sorry old bean but none of the above seems to apply at all to the OP's stated and shown (see scans) problem. He is observing black spots on prints/white spots (holes, lack of density) on the neg emulsion, you are talking about various effects which would lead to extra density on the neg.

There's no reason to expect the chemistry of a high energy impact with ionizing radiation to be anything like your usual picture of a electron meekly migrating to a sensitivity site while a hole is trapped. The effect I imagine would be more like obliterating a sensitivity site or a whole group of adjacent sites, the net effect perhaps more akin to solarization. And there are plenty of related two-event phenomena to consider i.e. the Herschel and Debot effects.

I don't know whether my theory about these films is correct, but it's not as easy to dismiss as you imply. From what I have read on the subject (including some of the links mentioned above), there is no systematic study, merely conjecture.

Anyway it sounds like a simple solution was found- don't use old film, and develop reasonably quickly, which is what Kodak clearly recommended in the first place.

Robert Hall · Sep 27, 2007

Yes, I have seen this on several IR HIE films and while we have never pinpointed the pinholes, we certainly have seen them.

With several calls to Kodak we have not gotten a credible response from them as to the cause.

Many blamed the stop bath being to acidic, but this is shear speculation and anecdotal with no supporting evidence.

Much of this went away with the new machines making the HIE in rolls and not making it in sheet anymore. (sigh)

But I know several people with 4x5 sheet film in the deep freeze who don't want to sell it and don't want to use it for fear of the pin holes.

This pin hole discussion, BTW, has been going on for 5 years now.

DaveOttawa · Sep 27, 2007

keithwms said:
There's no reason to expect the chemistry of a high energy impact with ionizing radiation to be anything like your usual picture of a electron meekly migrating to a sensitivity site while a hole is trapped. The effect I imagine would be more like obliterating a sensitivity site or a whole group of adjacent sites, the net effect perhaps more akin to solarization. And there are plenty of related two-event phenomena to consider i.e. the Herschel and Debot effects.

I don't know whether my theory about these films is correct, but it's not as easy to dismiss as you imply. From what I have read on the subject (including some of the links mentioned above), there is no systematic study, merely conjecture.

Anyway it sounds like a simple solution was found- don't use old film, and develop reasonably quickly, which is what Kodak clearly recommended in the first place.

My point was simply that all the influences you cite (essentially ionising radiation or visible electric discharges - i.e. sparks) will cause density to increase in the neg: the OP had a problem with lack of density.
I'd agree there is no readily findable systematic study of the "pinhole in HIE effect", but there are a number of empirical observations that suggest storage history of the film is the strongest factor.

loading IR in the light? use a tent?

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