Help identify black marks running across the top of 35mm negatives

O HanraHanrahan · Jun 3, 2024

Hello everyone,

I have recently developed 3 rolls of Ilford HP5 35mm film and on two of rolls have these black marks running across the top of 35mm negatives.

The marks only show on around 10 frames from one roll and around 13 frames on the other roll. The 3rd roll is perfect, no marks.

All 3 films were shot in the same camera.

I would greatly appreciate if anyone can identify what the issue is? Please see attached photos of the negatives.

Some information on my development process:
Developer Ilfotec DD-X 1:4
1000ml
9min @ 20° (-15% for continuous agitation)
7:39 min (Actual Development time)

Processed in a Paterson Multi-Reel 3 Tanks with Paterson Reels using continuous agitation in just one direction. (See attached video for the agitation process)

This was my first time experimenting with continuous agitation in just one rotation.

Kind regards,

Tadhg.

MattKing · Jun 3, 2024

Air bubbles or areas of localized increased agitation and flow.
I'd vote for the latter.
There isn't enough randomness imparted by the agitation process.

Melvin J Bramley · Jun 3, 2024

I have never had such results with continuous agitation.
The results are too even for air bubbles.

mshchem · Jun 3, 2024

Yeah, you need to go manual. Use the tank per manufacturer instructions.

Augustus Caesar · Jun 3, 2024

Surge marks from excessive agitation. Instead, fill the tank up almost completely, use manual agitation, invert tank with a twist twice once per minute.

koraks · Jun 4, 2024

O HanraHanrahan said:
The marks only show on around 10 frames from one roll and around 13 frames on the other roll.

Are the affected frames in the same general area on both rolls? I.e. at the start, end or somewhere in the middle?
Were these factory-rolled/confectioned rolls, or did you bulk load film into cassettes yourself?

O HanraHanrahan said:
(See attached video for the agitation process)

That's a remarkable contraption; do you use it in the dark at least up to the stop bath? Is it possible that the stop bath didn't entirely cover the film before the lights went on? Can you describe the process in detail a little more?

Melvin J Bramley said:
The results are too even for air bubbles.

Also the opposite density; bubbles tend to create lower density centers with higher density edges; like a netted pattern.

Augustus Caesar said:
Surge marks from excessive agitation.

Except that the agitation was in a longitudinal direction from the film's perspective, so surge marks would never have ended up this way. So no, that's not it.

A light leak problem seems most likely to me given the extent of the defect.

brbo · Jun 4, 2024

That is clearly a camera problem. The problem doesn't enter non-exposed part of the film.

koraks · Jun 4, 2024

brbo said:
That is clearly a camera problem. The problem doesn't enter non-exposed part of the film.

Good point, but in that case the interaction with the sprockets is inexplicable.

On second thought, I'd refix part of the affected frames and see if it makes a difference.

snusmumriken · Jun 4, 2024

koraks said:
Good point, but in that case the interaction with the sprockets is inexplicable.

On second thought, I'd refix part of the affected frames and see if it makes a difference.

In my experience, light getting onto tightly wound spools of film does produce marks that line up with the sprocket holes, but soft-edged streaks, not discrete round blobs. My money is on something preventing development, like air bubbles.

Surely further fixing cannot help, because the rebates are already crystal clear?

koraks · Jun 4, 2024

snusmumriken said:
My money is on something preventing development, like air bubbles.

But that would create minus density in the negative. This is plus density.

snusmumriken said:
Surely further fixing cannot help, because the rebates are already crystal clear?

Not necessarily; I've often noticed that silver halide fixes away much more slowly in places where there's developed silver density.

Ian Grant · Jun 4, 2024

As the increased development is clearly regular between the sprockets, it's down to the agitation method causing localised increased agitation. It's a wave effect along the yop edge.

Ian

brbo · Jun 4, 2024

koraks said:
Good point, but in that case the interaction with the sprockets is inexplicable.

Correlation does not imply causation. We have sprocket holes, a band of a few millimetres of film bellow that isn't affected at all, then heavily affected area that just by chance is limited exclusively to the area that gets exposed in camera?

If this really is a development issue it's the most bizarre I've ever seen posted anywhere...

I'd still have a look at the camera (bottom of the mirror box, near the film) and since OP did state that problem is not present on all frames I'd try figuring out whether frames that exhibit the problem have something in common (were all affected frames shot in bright conditions, etc.?).

Ian Grant · Jun 4, 2024

brbo said:
Correlation does not imply causation. We have sprocket holes, a band of a few millimetres of film bellow that isn't affected at all, then heavily affected area that just by chance is limited exclusively to the area that gets exposed in camera?

If this really is a development issue it's the most bizarre I've ever seen posted anywhere...

I'd still have a look at the camera (bottom of the mirror box, near the film) and since OP did state that problem is not present on all frames I'd try figuring out whether frames that exhibit the problem have something in common (were all affected frames shot in bright conditions, etc.?).

It's similar to over agitation when processing sheet film in a Paterson Orbital, or tray development, you can get over development of the film edges adjacent to the edges of the tank or tray. You can see why by just rocking a tray with water, you create a wave that bounces back of the edges.

You will get similar issues with over vigorous inversion agitation.

Ian

koraks · Jun 4, 2024

Ian Grant said:
or tray development, you can get over development of the film edges

I'm very familiar with this. I don't see how this would end up selectively on 10-13, frames on two out of three rolls, and only on one edge of the film.

pentaxuser · Jun 4, 2024

Melvin J Bramley said:
I have never had such results with continuous agitation.
The results are too even for air bubbles.

Yes that was my first thought as well. Whatever it is they are exactly the same size and spacing

pentaxuser

koraks said:
I'm very familiar with this. I don't see how this would end up selectively on 10-13, frames on two out of three rolls, and only on one edge of the film.

Yes that makes complete sense to me as well. It's a bit of a puzzle

pentaxuser

Ian Grant · Jun 4, 2024

koraks said:
I'm very familiar with this. I don't see how this would end up selectively on 10-13, frames on two out of three rolls, and only on one edge of the film.

It may be progressive, the outer part of the spiral is getting far more agitation, also the film may be looser. It may also depend on which way the spiral is loaded, ie clockwise or anticlockwise.

This way (anticlockwise), with clockwise agitation, will mean the first frames will be pushed outwards by the developer during rotation, that will increase development and most like accounts for the extra development between the sprocket holes.

However we theorise the issue it is down to the method of agitation, which also seems a bit too fast.

Ian

cliveh · Jun 4, 2024

In the video, is this an example of development agitation? Or, are you developing with no lid on the tank?

Don_ih · Jun 4, 2024

What camera? It could be the result of a defect in a vertical travel shutter. The phenomena is only occurring within the image frame. The edge markings are not impacted.

snusmumriken · Jun 4, 2024

koraks said:
But that would create minus density in the negative. This is plus density.

Ah yes, silly me, mental glitch.

koraks · Jun 4, 2024

Ian Grant said:
It may be progressive

Yeah, but the difference between what looks to be at least 0.5logD additional density and nothing at all is really beyond any reasonable bandwidth. Besides, I'm still struggling to see how with a rotary agitation method you'd get these sharply delineated 'bags' of plus density. Even with your centrifugal force argument I don't really see how this would work with Paterson reels and 35mm film. IDK really; it's weird. I'd still start with re-fixing since the only plus density anomalies I've ever seen with similar geometry were related to insufficient fixing.

Ian Grant · Jun 4, 2024

It cannot be a fixing issue as that would affect the rebates as well.

Ian

O HanraHanrahan · Jun 4, 2024

Hi everyone, thanks for all the replies.

Busy at the moment so can't reply to all the messages.

When I get home I will update ye and show ye more about how I developed the film.

koraks · Jun 4, 2024

Ian Grant said:
It cannot be a fixing issue as that would affect the rebates as well.

As I said above, fixing takes longer in areas with developed silver. It's possible in borderline situations that silver halide remains 'underneath' a silver image while it's already (just) fixed away in clear areas. I've encountered several instances of this phenomenon and it's also visible if you do fixing tests in daylight. Again, it would be a borderline/marginal situation.

O HanraHanrahan · Jun 4, 2024

koraks said:
Are the affected frames in the same general area on both rolls? I.e. at the start, end or somewhere in the middle?

The first roll it is mainly towards the end of the roll. On closer inspection the second roll has it on most frames to some degree and the third roll is completly fine. I've no idea what order they were in the tank.

I darkened the image so you can see the effect better.

koraks said:
Were these factory-rolled/confectioned rolls, or did you bulk load film into cassettes yourself?

They were factory rolled, not bulk rolled.

koraks said:
That's a remarkable contraption; do you use it in the dark at least up to the stop bath? Is it possible that the stop bath didn't entirely cover the film before the lights went on? Can you describe the process in detail a little more?

That contraption is an Automatic pot stirrer that I wanted to experiment with to automate my film processing. It was my first time trying it. I’ve been manually inverting / processing in Paterson tanks for years.

Yes, I put the Paterson light tight funnel on the tank before development.

Then I attached the agitator spindle and attached the automatic pot stirrer to the spindle/tank.

It has two speeds, I used the fastest.

I turned it on and then poured in the developer while the reels were being rotated / agitated.

I did not invert the tank or tap it to dislodge air bubbles.

I did the same for Stop and Fix process.

O HanraHanrahan · Jun 4, 2024

Melvin J Bramley said:
I have never had such results with continuous agitation.
The results are too even for air bubbles.

cliveh said:
In the video, is this an example of development agitation? Or, are you developing with no lid on the tank?

Yes that was just an example to show the speed and process. I had the light tight funnel on. I poured in the developer while the reels were spinning.

Help identify black marks running across the top of 35mm negatives

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