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  1. #31

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    I have a number of roll with the same history that are in canisters only and a lot more in their boxes and cellophane bricks of 10, all frozen. Hopefully the bricks have had less chance for moisture penetration - assuming thats part of the cause. Given this result was a little intermittent between the rolls, I am going to run a number of canister-only rolls of HP5, Delta 400 and FP4 through the camera with the lens cap on then develop them as a bit of a test on the remaining stock.

  2. #32
    Thomas Bertilsson's Avatar
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    Quote Originally Posted by craygc View Post
    I have a number of roll with the same history that are in canisters only and a lot more in their boxes and cellophane bricks of 10, all frozen. Hopefully the bricks have had less chance for moisture penetration - assuming thats part of the cause. Given this result was a little intermittent between the rolls, I am going to run a number of canister-only rolls of HP5, Delta 400 and FP4 through the camera with the lens cap on then develop them as a bit of a test on the remaining stock.
    When you say 'canister only' do you mean that the films are still in their factory plastic canister, or that it's just the bare metal cassette?

    When I freeze film I make sure the plastic canisters are firmly closed, and then I put five of them each in a small ziploc bag, and then as many of those small ziploc bags that I can fit into a big one. Maybe I'm being overtly protective of my film, but it has worked for me for many years now.
    "Often moments come looking for us". - Robert Frank

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  3. #33
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    Quote Originally Posted by polyglot View Post
    If you look at the edges of frame 13A, you can see that the exposure patterns curve into the centres of the sprocket holes and that there is no pattern to the right of each sprocket hole.
    I'm not arguing with your theory too much. I think it does have merit. However, let me add to what I proposed and see if it makes sense.

    There is a perception that film is always static. (Steady.) That is not always the case.
    In dealing with moving film for fifteen years, I have learned that the idea of film always being flat isn't necessarily true. When cinema film is projected, we often have the perception that it lies flat in the gate and it always stays straight and true. Yes, it needs to run straight and true as it moves through the projector but, in reality film projection is a very dynamic process. The film does buckle, jitter and weave as it it advanced through the machine but the trick is to make sure that it buckles, jitters or weaves into exactly the same position each time the projector's shutter opens. As long as the viewer's eye (visual system) acquires a congruent image, frame to frame, he will perceive it as being steady and in focus even when it isn't.

    In my hyptothesis, if the film was moving as it was advancing from one frame to the next, as it was being wound and rewound through a camera or if it was being loaded into its cartridge, the patterns of light and dark areas on the film could change. If the camera's sprockets were pushing against the film, it could cause a slight buckling around the sprocket holes which would cause the patterns to appear different.

    In fact, when diagnosing projector problems, a good technician should look at the sprocket holes of the film to see if there is any damage. A malfunctioning movie projector will cause permanent damage to the edges of the sprocket holes but, even if it is not, there is still stress to that area.

    In a still camera, there are pressure plates and different arrangements of the film aperture ("gate" or "trap" in the cinema world) which hold and transport the film differently but I still think it isn't always true to think that film is always static, regardless of whether it is a still camera or a cine camera.

    While I do agree with your theory that this could be caused by some form of triboluminescence or or mechanoluminescence, I also see evidence that the markings were caused as the film was moving. I think our theories mesh in these respects.
    Randy S.

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  4. #34
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    On taking a close look at the latest 'enlarged scans you posted... it appears that there has been some 'double exposures' made. Observe the gentleman sitting at the board on frame 15... Below his hand... at chair level there seems to be an image of a partial right foot. Since I have little medical anatomy experience... I have to question from "where could this 'foot' have come. other than by double exposure. To my eye, the 'regular' surge type marks around the sprocket holes are another other 'mystery' that I will leave open to the conjecture of someone else with a 'better eye'. My guess is that this film has gone through the camera more than once... but the first time, perhaps somewhat underexposed, but not 'fully re-wound back into the casette. The ''regular pattern' of what we (or I) can observe... perhaps as a 'closed' shower curtain might (when 'added' to the evidence of 'the foot') indicate a previous 'trip' through your camera.

    Ken
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  5. #35
    Nicholas Lindan's Avatar
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    Quote Originally Posted by polyglot View Post
    That makes me believe that it is either stress-exposure or triboluminescence (tape-ripping glow) caused by the film sticking together and then being pulled apart as it comes out of the cassette.
    I agree that it is some sort of triboluminescence effect. But if it were sticking to the film below then there should be some artifact of the second set of sprocket holes - the film can't stick to the hole beneath it.

    I noticed the second set of scans were both HP5. If this effect was confined to HP5 rolls then I think the finger points back at Ilford. If it is on HP5 and FP4 rolls then it is something that was common to the treatment of both rolls.

    The extreme consistency of the horizontal pattern is very puzzling, though there is some slight variation in spacing - which would indicate that it wasn't due to something scraping across the film but that some intermediate substrate was involved in transferring the pattern to the film. Say if adhesive is put down on tape by a set of nozzles and then the tape is applied to the film - even though it seems through protestations that tape is being ruled out.

    Whatever happened - it wasn't supposed to happen. Obviously something went wrong somewhere, so claims of 'we never do that' have to be taken with a grain of salt - somebody or something did do something that shouldn't have been done.

    Which leads me back to sticky tape getting where it shouldn't and then being pulled off with an 'oh, damn' without realizing the triboluminescence would image on the film.

    Murphy's law trumps all others.
    Last edited by Nicholas Lindan; 03-08-2013 at 01:23 PM. Click to view previous post history.
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  6. #36
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    Issues with negatives...

    I'll see your Murphy and raise you an Occam's razor.
    Randy S.

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  7. #37
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    Issues with negatives...

    I'll see your Murphy 's law and Occam's razor and raise you some chaos theory :-p


    ~Stone

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  8. #38

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    I haven't seen it mentioned but what type of developing tank (steel, plastic neither..) are you using and what's your step by step process ? Aside from the possible double exposure (see foot reference) I wonder if this could be something happening between steps ?

    If plastic, are you using that swirl stick ? Is there any chem leakage which could lead to light leak while processing ?

    Another thing, is you look at the first link at frame 28A-29, the artifacts by the sprocket holes change as the frame # increases. No idea what this could mean though but maybe a clue of some sort ?

  9. #39

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    Quote Originally Posted by canuhead View Post
    I haven't seen it mentioned but what type of developing tank (steel, plastic neither..) are you using and what's your step by step process ? Aside from the possible double exposure (see foot reference) I wonder if this could be something happening between steps ?

    If plastic, are you using that swirl stick ? Is there any chem leakage which could lead to light leak while processing ?

    Another thing, is you look at the first link at frame 28A-29, the artifacts by the sprocket holes change as the frame # increases. No idea what this could mean though but maybe a clue of some sort ?
    I use 2-reel Jobo tanks with their plastic reels - no swirl stick involved. Process was everything in the tent (tank, lid, center tube and 2 reels; film canisters - leader already out, kids round nose scissors). Leader is cut square with small bevel on the corners before going in the tent; I take my watch off to get my hands in the tent sleeves to avoid light leaks; the negs went on the reels very easily and when cut from the canister it continued into the reel with little effort (no loading issues); first reel placed on the center post on inside the tank; second reel place on the center post without removing it from the tank; lid locked on (always note its tight); hands out, unzipped then everything out. Film sat in tanks over night.

    Chemicals mixed up next morning and adjusted to 25 degrees celsius (too hot in Singapore to attempt 20). Then its just chems in and out with inversions as usual. Developer doesn't leak at all; fixer leaks a little but always has (from the rubber chemical cap). When finished with fixer, tank lid off, rinsed for another 10 mins with flowing water; hung to dry for half a day; then cut and sleeved. Nothing really out of the ordinary. What I don't know is whether the affect rolls were developed in the same tank - I loaded 2 (4 rolls) at the same time.
    Last edited by craygc; 03-09-2013 at 04:41 AM. Click to view previous post history.

  10. #40
    MattKing's Avatar
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    25C developer temperature might be relevant to the problem.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

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