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John Layton
25-Oct-2018, 05:48
My problem is the condensation which can form on my sheet film when I’m working in truly moist environments - where such moisture is often accompanied by sudden temperature changes…conditions I often encounter when I’m photographing surf.

It is the difficulty of my getting to these locations for more than a brief few days each year - plus the rarity, when on location, of actually encountering my “preferred conditions”…which themselves tend to facilitate condensation - plus the chaotic nature of my subject itself, which makes (with or without condensation) satisfactory results very “hard won” - which makes this condensation issue so very frustrating.

(Its also not too uncommon for a wave to break over me and all my gear as I’m under my dark cloth…being distracted by whatever it is I’m finding so distracting - so there is that).

At any rate…I typically carry my film (5x7 TMY in this case) in two RPT “Cascade” cases, with each cassette having been wrapped in a Ziplock bag prior to being zipped into its individual compartment. I do remove the “zippers” from the bags, as this make logistics much easier - but the bags themselves are carefully folded over the cassettes in a way that makes me doubt that (much) moisture could find its way in.

So I’m left thinking that I’m working right at some confluence of temperature and humidity which facilitates condensate forming on the film’s surface - obviously prior to making an image (can condensate which forms post-exposure cause a reduction in density? I don’t think so).

What I’m seeing on my films are either lighter (less dense) blotches with frilly edges (indicating a wiping motion and/or evaporation) or figures which look a bit like… jellyfish?, consistently shaped and relatively well defined - like what might be left after a dark slide has bowed slightly inward and outward during handling, making contact with moist film (or a moist dark slide and dry film?), leaving “water prints” on the film’s surface in the process. In fact, these “jellyfish” tend to occur away from the edges of a dark slide, more toward the middle - where such movement would be more likely to occur, while the “wiped blotches” tend to form closer to the edges, where the contact would not be so direct.

Finally…while my latest “condensation crisis” occurred while using TMY film, this issue seems somewhat less frequent/apparent when using FP-4. Would there be a reason for this?

So…any thoughts/suggestions/ideas? Thanks! Oh…and here are a couple of examples of photos which may give some indication of my “preferred working environment,” which unfortunately tends to lead to condensation:
183666183667183668

Bruce Watson
25-Oct-2018, 06:39
So I’m left thinking that I’m working right at some confluence of temperature and humidity which facilitates condensate forming on the film’s surface...

Yup. It's called the dew point (https://en.wikipedia.org/wiki/Dew_point).


Finally…while my latest “condensation crisis” occurred while using TMY film, this issue seems somewhat less frequent/apparent when using FP-4. Would there be a reason for this?

Maybe. I believe I've read that some older films (Ilford?) incorporated a wetting agent in the emulsion to promote more consistent development. If true for FP-4 Plus, this might have the effect of reducing the surface tension of any condensate, causing any condensate "drops" to be flatter, more spread out, and having less well defined edges.

Pere Casals
25-Oct-2018, 06:54
Hello John,

I guess that next procedure should address any condensation:

1) At home: Keep holders inside a plastic zipper bag (perhaps one bag per holder), throw in "dry air" (that to clean computers) and a little bag of silicagel. This will absolutely prevent condensation until you open the zipper bag.

2) In the shooting location, the holder has to be relatively hot compared to ambient air, so you can store all holders (that were at room temperature) in a Insulated Thermal Bag (those for frozen sea food shopping ), you can place also inside a bottle with hot water to keep it warm long enough.

For example if you keep a holder in the car's trunk all (freezing) night long, and then you expose it then the sourronding air decreases its temperature, this may led to condensation, as the metallic septum has thermal inertia.

So at least holders should be trasported inside the car's habitacle, to get warm.

Ted R
25-Oct-2018, 16:13
Great pics, I like #1 especially, clearly moving water.

It isn't clear that condensation is the problem. If I understand correctly condensation forms in one condition and only one condition, when a surface that is lower in temperature than ambient is exposed to ambient air, some of the water vapor in the air condenses on the cooler surface. Why would the film be cooler than ambient? Are you shooting in the tropics?

I agree with Pere's suggestion to maintain the loaded holders at a temperature higher than the ambient where you are headed, and keep them warmer than ambient until loaded in the camera. The loaded holder will cool slowly but will never become colder than ambient.

John Layton
25-Oct-2018, 16:28
Maine/NH coasts - but moisture conditions would indeed rival those of the tropics...and temps can quickly jump when the sun pokes through even for a brief time as it often does. I also suppose, as I've been photographing in similar conditions for quite awhile and yet this problem has suddenly cropped up...that this particular batch of (special order) 5x7 TMY could be defective in some way. Would be a bummer...but laying on emulsions, even in "factory" conditions - can be a moving target...and smallish, intermittent, special order runs could, I might guess, present some serious challenges to consistency and QC. Speculative I do admit...but it just might be time to get back to my consistent and trusty FP-4.

Sal Santamaura
25-Oct-2018, 17:04
...smallish, intermittent, special order runs could, I might guess, present some serious challenges to consistency and QC...

The only thong "special" about that 5x7 TMY-2 order was cutting and packaging. It comes from the same master rolls that all other TMY-2 sheet film do, including 4x5 and 8x10.

Mark Sampson
25-Oct-2018, 17:12
All a 'special order' consists of is custom slitting and packaging of part of a 40" wide master roll. Your 5x7 film is the same as the current 4x5 and 8x10 films. So I doubt that your problem is related to that. It may be that TMY is more susceptible to your condensation, but I doubt Kodak tested for that. They would tell you to keep your film dry. If there is a wetting agent in the emulsion of any film (I have no idea), it would be unlikely to have any effect unless the emulsion was soaked.
Do you have images that show the problem?
If waves are breaking over you and your camera, I'm not sure there's much you can do to keep your film dry throughout your shooting session.

Mark Sampson
25-Oct-2018, 18:10
I should also add that I admire your persistence and dedication.

LabRat
25-Oct-2018, 18:15
Are you loading/unloading in a changing bag or tent with sweaty hands and arms inside???

That's when it happened to me...

Steve K

Willie
25-Oct-2018, 18:31
Might try what we use for winter and night sky photography to keep condensation from lens surfaces. The shake/dry pack hand and foot warmers - the chemical kind that heat up and stay that way for a few hours. Set one under the lens and it doesn't get dew on it for long night exposures. Maybe could put it under the film back area?
With battery driven cameras we gaffer tape them under the motor/battery section so they last longer. Talking temps to 45 below zero here but mainly 0 to 20 below more often.

John Layton
25-Oct-2018, 18:47
Thanks for educating me about Kodak special orders...sorry if I stepped on any toes and I should probably be thankful that I can still find this film. But I'm still a little suspicious as I've been doing this for so long and only now am seeing what seems to be a disproportionately high number of "condensation" artifacts. At any rate...I think I'll go out "into the dampness," set up my camera, go through all the usual motions of making an exposure, then pull a dark slide or two and see what's what.

Mark Sampson
25-Oct-2018, 19:18
None of my toes stepped on; you've got a problem and I was just trying to narrow down your search for the answer. My own recent experience says that there are few things more frustrating than such unexplained artifacts, so I can sympathize. I don't have any better ideas, but I wish you the best of luck in solving it.

David Lobato
25-Oct-2018, 20:03
In my old job I did a bit of analytical work on humidity and condensation with respect to the dewpoint. If your film and film holders are a few degrees warmer than the outside air, condensation should not form on the film. Condensation happens when your film and film holders are at a cooler temperature than the outside air. It applies to any surface, like lenses too. That's why astronomic photographers use warming devices on their lenses during the night to prevent condensation. So, keep your film in a warm area before venturing out. And maybe keep them in an insulated cooler with a warm bottle of water or chemical hand warmers, like Wilie suggested.

cowanw
26-Oct-2018, 06:30
Could it be that coming into a warm area after you are done is the problem.