Strange problem with my developed film

Sharktooth · Aug 19, 2023

The key issue here is that it has now happened with two different cameras. It's unlikely that both cameras have the exact same problem.

If it's not a camera issue, then it could be an issue with the film itself, or with handling of the film outside the camera.

It's extremely unlikely to be an issue with the film, as Ilford is a reliable supplier, so that leaves film handling outside the camera as the most likely suspect. The most likely issues here are getting the film into the developing tank, and the developing tank itself. Changing bags are the most likely suspect here, since that's what's being used to transfer the film into the tank.

Here's a good example from a thread at the Large Format Photography Forum: Is this light leak on my negatives?
In this example, the original poster was using sheet film and finding strange light leaks. He did multiple expensive tests to try and determine the problem. but eventually discovered that it was the changing bag at fault. He discounted the changing bag earlier, since it had never been a problem before, but when he finally went to check it he found that it was easy to see that it wasn't light tight anymore.

If I was a betting man I'd put money on this for sure.

koraks · Aug 19, 2023

Again, the pattern of the fogging matters. The sheet film example you linked to doesn't compare. How does a leaky changing bag result in consistent fogging in a very specific place on the film in a very specific pattern, leaving the rest unaffected? The answer is, it doesn't.

AnselMortensen · Aug 19, 2023

logan2z said:
It's certainly worth a try. I'll be loading another roll today and I'll do it with the changing bag in the dark.

Make sure your eyes are closed, too!

Sirius Glass · Aug 19, 2023

logan2z said:
Quick update: I just developed another roll of the same film (HP5+) shot with a different camera and the same thing happened - some sort of fogging of the leader up to and including the first frame. All other frames look ok, as far as I can tell (the film is still hanging to dry).

One thing I didn't mention earlier in this thread: I don't fully rewind the film into the cassette but I leave the leader out so that I can trim the corners in daylight before loading it onto the reel. I also prefer to load the reel directly from the cassette rather than opening the cassette and taking the film roll out in the changing bag. One thing that @250swb suggested to me on another forum is that this could lead to light piping. I thought that was pretty rare and only affected films with a polyester base. Also, as soon as I unload the film from the camera, I put it right into the black opaque canister that the film comes in, so the film cassette is not exposed to light with the leader sticking out for more than a few seconds. I've been doing this same thing for quite a while now and have never had this issue crop up.

I'll guess I'll shoot a roll of a different film and see if this is somehow related to the batch of HP5 I'm using.

I guess the good news is there doesn't appear to be anything wrong with my M2.

Leave only an inch or two [2 to 5cm] and store in a black, light tight container.

logan2z · Aug 19, 2023

Sirius Glass said:
Leave only an inch or two [2 to 5cm] and store in a black, light tight container.

That's exactly what I do.

logan2z · Aug 20, 2023

Here's a couple of photos of my last roll.

The first photo shows the beginning of the roll and the observed fogging pattern. I've seen a similar pattern on some other recent rolls.

The second photo shows that there is some fogging around the sprocket holes of later frames as well - it looks like the fogging is mirroring the sprocket holes. Maybe light reflections from the socket holes themselves? By around frame 6 there is no signs of fogging around the sprocket holes, or anywhere else.

Again, I was lucky that only the first frame had any fogging within the image area.

It was suggested a few posts above that this could be caused by a light leak in my changing bag. I'm skeptical of this given that the issue only seems to affect the early part of the roll, but I guess I'll use the changing bag in an almost dark room to load my next roll onto the developing reel and see if that makes any difference.

Sharktooth · Aug 20, 2023

I'm still betting on the changing bag, but it could also be an issue with the tank.

If you're using a Patterson or Jobo tank with a center reel core post, then the post could be badly cracked. This assumes you're loading the film leader into the roll first. That would put the leader closest to the center core, and more likely to be exposed if the core post is cracked. The rest of the film has greater protection since it is further from the core, and protected by the other layers of film.

logan2z · Aug 20, 2023

Sharktooth said:
I'm still betting on the changing bag, but it could also be an issue with the tank.

If you're using a Patterson or Jobo tank with a center reel core post, then the post could be badly cracked. This assumes you're loading the film leader into the roll first. That would put the leader closest to the center core, and more likely to be exposed if the core post is cracked. The rest of the film has greater protection since it is further from the core, and protected by the other layers of film.

I just closely examined the center post of both of my Jobo 1520 tanks and don't see any signs of cracking. I examined the tanks themselves as well, no cracks. Good suggestion, though.

And, yes, I am loading the leader onto the reel first.

koraks · Aug 20, 2023

Is there any possibility that the cassette experiences lateral pressure during loading or when fitttled inside the camera? This might push the light trap open slightly, causing a light leak.

An interesting hint is that the leak seems to be worst at the top end of the film, i.e. the edge that points upward when the film is inserted into the camera.

logan2z · Aug 20, 2023

koraks said:
Is there any possibility that the cassette experiences lateral pressure during loading or when fitttled inside the camera?

That's an interesting thought, but I don't see how that would happen with the cameras I've been using. Essentially you just drop the cassette into the camera, pull out enough leader to reach the takeup spool, make sure the sprockets are engaged in the sprocket holes, and close the camera back. Then wind on a few times and you're done. I don't see how there would be any lateral pressure applied to the cassette during the loading process.

MattKing · Aug 20, 2023

Do you have a spare roll of unexposed film - long expired would be fine - that you could develop and then check for the fogging?

koraks · Aug 20, 2023

logan2z said:
pull out enough leader to reach the takeup spool

Upon pulling out the leader, it is at least theoretically possible that this exerts a force on one side of the felt light trap, pulling it slightly open. This would fog the first few frames, and the pattern of the fogging could well be consistent with what you're getting as the pull force on the film leader will vary a bit.

logan2z · Aug 20, 2023

koraks said:
Upon pulling out the leader, it is at least theoretically possible that this exerts a force on one side of the felt light trap, pulling it slightly open. This would fog the first few frames, and the pattern of the fogging could well be consistent with what you're getting as the pull force on the film leader will vary a bit.

I guess that is theoretically possible, although I don't understand why that would suddenly start happening when I've been loading these cameras and this film the same way for a long time. The whole thing is a little baffling.

koraks · Aug 20, 2023

Yes, it is. Baffling phenomena ask for baffling explanations! I'm also puzzled.

logan2z · Aug 20, 2023

koraks said:
Yes, it is. Baffling phenomena ask for baffling explanations! I'm also puzzled.

I'm leaning towards defective light traps in a batch of cassettes, but I realize that's a long shot. Looking forward to seeing what Ilford says when they reply to my email.

madNbad · Aug 20, 2023

I rewind the leader into the cassette then use a retriever to pull it out, trim it, load the reel from the cassette and haven't had a problem with scratches. Faulty light traps wouldn't be a surprise but at least it's not making it into the image.
Is your M2 still difficult to rewind?

logan2z · Aug 20, 2023

madNbad said:
I rewind the leader into the cassette then use a retriever to pull it out, trim it, load the reel from the cassette and haven't had a problem with scratches.

I used to fully rewind the film and use a retriever to pull out the leader, but I figured that shoving something into the cassette through the light trap would be more likely to cause light leaks

madNbad said:
Faulty light traps wouldn't be a surprise but at least it's not making it into the image.

Unfortunately it is making it into the image. Usually just the first one, however.

madNbad said:
Is your M2 still difficult to rewind?

It's not difficult to rewind the film most of the way, it only requires more force than I'd expect to get the film released from the takeup spool.

Arvee · Aug 20, 2023

I got those exact marks in exactly the same place; I finally figured out that I was wearing my Fitbit while I was loading the film on the reel. The digital watch was momentarily illuminating and generated enough light in the changing bag to fog the film. Problem disappeared when I stopped wearing the watch when I develop film.

logan2z · Aug 20, 2023

Arvee said:
I got those exact marks in exactly the same place; I finally figured out that I was wearing my Fitbit while I was loading the film on the reel. The digital watch was momentarily illuminating and generated enough light in the changing bag to fog the film. Problem disappeared when I stopped wearing the watch when I develop film.

Interesting. But I always make sure I'm not wearing a watch while I load film onto the reel in the changing bag.

But I am going to examine my changing bag for possible light leaks.

Arvee · Aug 20, 2023

logan2z said:
Interesting. But I always make sure I'm not wearing a watch while I load film onto the reel in the changing bag.

But I am going to examine my changing bag for possible light leaks.

Many years ago I had similar markings; these were caused by light leaking by the elastic in the arm holes. I have since done all my tank loading in the changing bag in the darkroom with lights off. Problem solved.

logan2z · Aug 20, 2023

Arvee said:
Many years ago I had similar markings; these were caused by light leaking by the elastic in the arm holes. I have since done all my tank loading in the changing bag in the darkroom with lights off. Problem solved.

That's an interesting one for a couple of reasons:

1) If I look at the shape of the cross section of the elasticized arm holes, they look a lot like the shape of the fogging pattern I'm seeing.

2) It just occurred to me that I have recently been loading the tank wearing short sleeves, whereas I waa wearing long sleeves before. I wonder if the elastic is giving out in the arm holes and letting light leak in but they were sealing sufficiently to my arms when wearing long sleeves. Now that I've switched to short sleeves they are not. Crazy theory?

I've just loaded some film onto the reel in my changing bag in near-complete darkness wearing long sleeves Going to develop it now and we'll see what happens.

logan2z · Aug 20, 2023

I just developed another roll that was loaded onto the reel in the changing bag in tbe dark (while I was wearing long sleeves ) and ...

No leak! The start of the roll is completely clear.

I would have never guessed it was something to do with the changing bag given the localized nature of the leak, but I was obviously wrong.

Thanks to @Sharktooth and @Arvee for pointing me in the right direction, and everyone else (@koraks etc ) who offered help. Much appreciated!

mshchem · Aug 20, 2023

Yeah Forum!!!

Sharktooth · Aug 20, 2023

Take a bright flashlight and put it in your changing bag. At night, turn off the lights and put your hands in the bag and turn the flashlight on. Move the flashlight around and see if you can see any light shining through.

Open the bag and shake out any loose material onto a light colored sheet or towel. Check for small black flakes. That will be deteriorated rubber coating.

logan2z · Aug 20, 2023

Sharktooth said:
Take a bright flashlight and put it in your changing bag. At night, turn off the lights and put your hands in the bag and turn the flashlight on. Move the flashlight around and see if you can see any light shining through.

Did that earlier today. I can see light shining through the bag all over the place! This bag is barely a year old, I'm surprised it would go bad so quickly. I'll look for another of better quality

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