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What could have caused this? Portra 400

Duceman

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Did some color negative developing this past weekend and had one roll come out with some problems I've never seen before. Don't think it is the chemicals, because I did a couple of rolls after this that seem fine.

This is from a 36-exposure roll of Portra 400. And this is essentially the tail end of the roll... interestingly, the first dozen or so frames, while exhibiting some issues, are at least salvageable whereas these are not. I can't determine if this is because of: Light leaks? X-rays? Problem with film in canister? Problem with film in camera? Overdeveloped?

I should also mention that I personally did not shoot these shots; they were shot by a friend of mine to whom I lent a camera (Minolta XG-7) and said I'd develop/scan the film for him.

First shot is a photo of two strips of the negatives:



Second shot is the above photo after being inverted and adjusting levels... notice the vertical flares extending about the sprocket holes... to me this is a clue, but I can't figure out what could have caused it.

 
This looks like a light leak to me. Perhaps degraded seals? The mostly monochromatic nature is a bit odd, but could be explained by the conditions the camera was kept in, filtering specific wavelengths (e.g. a red carrying bag).
 
I was thinking that if the first shots were less affected, it could be because they were being wound (and protected) on the winding spool, and that whatever did this had to have occurred later in the shooting (as I didn't shoot these, I don't know how long it was between shots or how long from the first frames to the last frames). But the sprocket flare is what has me scratching my head; if it were light leaks, wouldn't it be more uniform across the film plane? Also, I'll have to check my records, but I think the seals were replaced in this camera within the last year or two, so not that old.
 
Nice puzzle! The end of the film would have been towards the inner part of the cassette, but the outer part of the spiral in the tank. I suppose it would also have been outwards on the take-up spool in the camera, so would have had the worst of it if the back was opened inadvertently - but I’ve done that a few times, and this doesn’t really look like that kind of accident to me. If it is an auto-rewind camera (?) that would be irrelevant anyway. And the sprocket holes would not be aligned when the film was tightly wound in the cassette or on the take-up spool, so it seems unlikely you’d get such an even effect. Weird too how those red streaks appear to be evenly spaced but not consistently present.
 
In a color negative film, orange streaks of the color of the vertical lines in the positive image suggest a light leak through the back of the film.

Many cameras wind the film inside out on the takeup spool, so a light leak somewhere in the back may expose through the back while in the film gate, and through the front while on the spool.

Perhaps the film was exposed to light (insufficiently closed back?) while wound on the spool and that's why there is streaking around the sprocket holes. Kind of reaching here as I'm not sure it's one single leak causing all the phenomena.
 
I've seen this when the film was wound 'backwards' into the cassette, turning the rewind knob counterclockwise instead of clockwise. If you search 'film stress marks' it looks exactly like your sample.
 
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I second the "rewound backwards" hypothesis.
Ex-photolab guy here, I've seen that a lot.
 
The "rewound backwards" hypothesis may be it. I did notice that the film appeared to be "bent" a few inches behind the leader (approximately on the second or third frame), but wouldn't that mean that first few frames would have been the worst, as opposed to the end ones?
 
sharper bend when the size of the roll os Smaller near the core of the spool. Yes, I would go also with the wound backwards theory. Does the film have any wrinkles or does it lay flat.
 
Duceman said:
But the sprocket flare is what has me scratching my head; if it were light leaks, wouldn't it be more uniform across the film plane?
Click to expand...
I was thinking of light piping.

But if the 'rewound backwards' pattern is a better match, I'd look into that. I've never seen it myself, but I can sort of imagine how it might work.
 
I agree with @Dirb9 and @AnselMortensen . (I am also ex photo lab)

The stress marks have caused the marks to come from the sprocket holes.
There also appears to be a light leak at regular intervals, which would suggest a light leak in the film cassette or camera.

To my eyes, the film looks underexposed and slightly underdeveloped.
 
Well... looks like mystery has been solved. Thanks for all the help!
 
Interesting - I haven't ever done or seen this myself. I suppose that the stress marks come from pulling the film over a corner, causing it to buckle at the sprocket holes. Guessing that it happens as the film is pulled over the inside of the cassette lip?
 

All you have to do is to rewind the film the other way. On most cameras, you would rewind the film clockwise. Instead, rewind it anti clockwise. Develop the film and admire your results.
 
I have an auto rewind camera so this cannot happen but what puzzles me is how can you rewind it backwards and still get the film back into the cassette? Once you press the unlock pin that allows the manual rewind lever to turn freely then assuming its possible to turn it both ways, wouldn't turning it the wrong way simply not do anything to move the film at all and if it wasn't obvious that something was wrong then on opening the back there would be film that would be unwound and buckled against the back of the camera ?

Thanks

pentaxuser
 

It will still rewind, albeit with a lot more force required, since the film would be bent like "Ƨ" instead of regular "C", due to the reversed direction of rewinding. And of course the side which is supposed to be bent inwards (emulsion side) would bend outward, hence the stress.

The way the film is attached to the core of the cassette, be it the Kodak method, or Ilford method, allows such a travesty.
 
Also worthy of note -- many cameras withy manual rewind have a screw thread attachment for the rewind crank -- turning it the wrong way, especially with higher than normal resistance, risks having it unscrew. This can make it difficult to open the back (especially in the dark, trying to save the rest of the film still on the takeup and in the gate), since many of these use the rewind crank as the back latch release. Generally there's an arrow on the knob or crank; turn that direction to rewind.
 
It will only unscrew if something's holding the rewind shaft. Serious tension from something like a screwdriver lodged between the teeth, when one is trying to disassemble the rewind mechanism, OR a serious tension from film that is already rewound the wrong way.
 

Thanks, it may be that I am spatially challenged in the sense of having difficulty in envisaging exactly is happening in your above explanation but I am still having difficulty

I am assuming that the cassette has reached its "empty" point so another turn of the wind-on lever meets the kind of resistance that makes it clear there is no more film to unwind.

The release pin has been pressed which I presume allows the rewind crank to turn either way and the user then turns the rewind crank "backwards" or anti-clockwise looking at it from the top. I presume this forms an initial kink in the film which takes up some extra space in the cassette and by this time there would be extra force required which we are assuming is not sufficient to make the user realise something is wrong. If the user has never rewound film then maybe he was oblivious of the extra force that must have been then required.The film is now, as you say, bent outwards

Is this initial space formed by the kink or "2" shape not enough to prevent all the film entering the cassette and does it stress the emulsion enough to make these very clear and parallel looking lines in the film?

Finally I would have thought that if backward rewinding is easy enough to do and create this kind of damage the incidence of it would be of such a frequency that some kind of a failsafe mechanism would be built-in to prevent this?

Finally why isn't it the last few frames that are most affected as it is these that are the ones initially stressed more as it is these that bent more sharply that the last few when the film describes a bigger circumference around the cassette's spool?

I should just ask: What problems would this wrongly rewound film have given the person who had wind it onto the developing reel? For instance could you do it with a film retriever and if so would you notice it as you fed it into the reel?

If on the other hand you levered off the top of the cassette and took the film spindle out of the cassette would you notice that the film was the wrong way round?


OP, depending on the answers to these last two questions can I ask what problems, if any, you experienced when retrieving the film? I take it when you got the film back the person had already rewound it. If so it might make sense to ask him/her what difficulties he/she experienced in the rewind?

Thanks

pentaxuser
 

Only difficulty I had was I was unable to pull out the leader with a retriever tool (which itself is not out of the ordinary). I therefore used a tool to pry open the top and take the film out (in change bag). Nothing felt out of the ordinary... film went onto reel in a normal fashion. It wasn't until I pulled the reel out of the tank after developing, and looking at the film, did I notice anything wrong. Oh, there was also a bit of a crease in the film, which I mentioned in post #8 above.

I have reached out to my friend, who doesn't recall doing anything out of the ordinary, but I'm sure he simply can't remember what direction he ran the rewind lever. I've told him to be careful about this in the future, and to be sure to look at the arrow on the underside of the lever as a reminder as to which direction to turn the lever on rewind.
 
Duceman said:
be sure to look at the arrow on the underside of the lever as a reminder as to which direction to turn the lever on rewind.
Click to expand...

This. Even If the instructions don't have any words, follow them unless you know why you shouldn't.
 

Thanks. As I said I have no experience of non auto-rewind cameras - well a Yashicamat many years ago but I may have never rewound it backwards -well not unless the rewind action was nearly as easy as the correct way and by all accounts from others here this seems unlikely. So based on everything you describe in terms of what you did and the user did I am left with a nagging doubt about why neither of you noticed anything difficult unless it indicates that the rewind backwards may not have been the cause

pentaxuser
 
pentaxuser said:
...I am left with a nagging doubt about why neither of you noticed anything difficult unless it indicates that the rewind backwards may not have been the cause
Click to expand...

What exactly are you doubting?

And what exactly on my end should have been difficult?
 
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