Bubble marks across part of negative (not the continuous edge marks)

[Tom Kershaw]

Today I came across a fault with my Jobo / Pyrocat-HD processing regime that I've never experienced before. When using Paterson tanks I had issues with a continuos line of air bubbles throughout the entire length of the film (well documented on APUG), which I no longer get after returning to use a stop bath (not scientifically tested), however this Jobo processing fault is very different:

From the four films developed in the batch, only this film shows the fault; on two frames.

Technical specs:

• 2 minutes pre-soak as part of the Jobo ATL-2300 program (mains water)
• Pyrocat-HD 1:1:100 - 1000ml solution. (mixed with de-ionized water)
• Developing 4 rolls of ILFORD DELTA 400 film
• No stop bath, and an Alkali fix (Fotospeed FX40)
  
• A dilute solution (approx. 75% of the recommended dose of Ilfotol) and de-ionized water into the tank, before being poured out and the developing tank washed out with several changes of water.

In the last few days I have processed around 30 rolls of Delta 400 in the Jobo and have noticed this fault on two films (at first glances / contact sheets).

The only major difference between batches is that for the development batch under discussion only 4 reels were present in the tank, whereas 5 reels (one empty) were present on most of the other batches.

Tom

 

[dwdmguy]

Tom, I'm a 2300 user also. (few of us, huh?)

I can't see where there would be an issue with the Jobo unless you changed the RPM setting which I doubt you did.

 

[Tom Kershaw]

Tom, I'm a 2300 user also. (few of us, huh?)

I can't see where there would be an issue with the Jobo unless you changed the RPM setting which I doubt you did.

I should have added that I'm developing with Pyrocat-HD at the 50 r.p.m setting. In terms of reducing variables, I may experiment with going straight to the developer without a pre-rinse, and adding a stop bath, rather than a plain one minute rinse, between the developer and fixer.

I'm using a 2500 series tank.

Tom

 

[Tom Kershaw]

Has nobody seen this development issue before?

Tom

 

[Willie Jan]

could it be that your tank had some wetting agent residu left inside?

 

[Tom Kershaw]

Willie,

Yes that may be the case, and might account for the occasional nature of the fault.

One question might be whether the pre-rinse stage is contributing to the problem due to variable water quality from a photographic processing perspective, or possibly a longer pre-rinse might help to wash out any residual wetting agent..

Here is the other example from the same film:

The scanner hasn't coped well with the print density but you can see the issue, albeit with a different pattern.

Tom.

 

[Mick Fagan]

Tom, I have seen similar things, but they weren't developing problems, they were in the final bath.

You appear to be doing your final bath with the film on the reel(s) inside the tank.

I understand that you are then washing out the final bath with fresh water, sort of defeats the purpose I would have thought.

Effectively if you run a wetting agent through a Jobo tank, whether that is on the machine and turning, or off the machine and inversion, or whatever agitation is used, you are making soap bubbles, either moderately or very seriously.

My preferred method of wetting agent bath for both B&W and C41 (stabiliser) is to do it outside the tank and off the reel.

By keeping the reels out of the equation you should be able to keep sudsing, (best term I can think of) to a minimum.

I use a 1 litre plastic jug with 500ml of wetting agent or stabiliser (C41) with 35mm film. I do this by pulling the reel apart and dropping the coiled film sideways into the jug.

With 120 or 4x5" film I use the same amount of solution, but use a 5x7" dish/tray and with 120 see-saw slowly, with 4x5" I hold the film by the edges and never let it touch the bottom and gently rock it back and forth to ensure an evenness of solution can get to the emulsion.

In both cases I use 1 minute as the maximum time before puling out.

I then hang the film up to dry.

Looks like dried soap bubbles, are they on adjoining frames?

Mick.

 

[Willie Jan]

some time ago I had problems with strange marks at the side of the neg where it is attached to the spiral.

I cleaned the spiral and the problem was gone.

I now never use wetting agent in my tank.
I have a dedicated cup where i mix the wetting agent and take the film off the real and put it in this cup for a minute.
This will leave my tank clean...

 

[arigram]

I think it has to do with the developer.
I have seen it before, as in this photograph of mine, developed in a lab where the whole negative had this band of bubbles:

I am not sure causes it exactly though.

 

[Tom Kershaw]

Mick,

Thanks for the response. I should make clear that my final bath is de-ionized water with less than the ILFORD recommendation of wetting agent added. These aren't drying marks, but look like marks created during the development stage (which could be bubbles caused by soap / wetting agent), i.e. the film is physically clean.

Looks like dried soap bubbles, are they on adjoining frames?

Mick.

No, the marks are restricted to individual frames (16 on a film, strips of 4)

 

[Neal]

Dear Tom,

2 WAGs that I have little faith in...

1: Wetting agent was bubbled up and allowed to dry on the film. Maybe a long soak will reduce them.

2: The missing reels resulted in a slightly lower fluid level and the bubbles were allowed to sit on the film during processing.


BTW: I always use my Jobo at 75 (78?) rpm. Never a problem.

Good luck,

Neal Wydra

 

[Tom Kershaw]

I think it has to do with the developer.
I have seen it before, as in this photograph of mine, developed in a lab where the whole negative had this band of bubbles:

I am not sure causes it exactly though.

The whole roll of film? I've never experienced the small continuos band of small bubbles on the side of the film you can with Paterson tank processing with Jobo processed film.

Tom.

 

[Willie Jan]

The wetting agent can cause the developing to act differently than on the film where no agent is sticked to it.

Looks like it prevents the developer to get into the emulsion.

 

[Tom Kershaw]

The wetting agent can cause the developing to act differently than on the film where no agent is sticked to it.

Looks like it prevents the developer to get into the emulsion.

Perhaps different agitation or processing methods result in different patterns, but with the same or similar cause.

 

[Bruce Watson]

My CPP-2 was contaminated with color film wetting agent by the previous owner. I didn't know this until I used it the first time with my nice new 3010 tank. When I opened the tank up after processing I found this odd white froth of bubbles.

Turns out that you can't ever fully remove wetting agents from processors or tanks. So I still get some sudsing six years later.

Here's the deal -- film seems to be susceptible to density marking like this when it's first dunked into the developer. IOW, it's important to get a nice even coating of developer all across the film, all at the same time. A few seconds difference and you see density marks, no matter how long the film spends in the developer.

The frothing that takes place inside the tank due to the residual wetting agent can act like a kind of shield to keep the developer off the film for a few turns of the tank. And that can be enough to create the markings you are seeing.

One thing you can do is slow the rotations down. This will have the twin benefits of slowing down the formation of bubbles, and slowing the oxidation of the developer. It will also tend to lengthen your processing time a bit depending on how slow you go. Just sayin'.

I've never found a way to get the wetting agent out of my Jobo system. It's pernicious stuff; very hard to get rid of. But the first step is to stop running it through your Jobo and tanks. Do your final wetting agent rinse in another tray or tank off the Jobo.

I've never run wetting agent through my Jobo, and over the years the amount of sudsing has decreased markedly. But it's not gone, and no amount of scrubbing by me has been able to remove it completely.

 

[Tom Kershaw]

Bruce,

Thank you for your response. I have been using the wetting agent bath off the Jobo but within the tank, and with the film still loaded on the reels. As my unit is the ATL-2300 the solution timing is automatically handled by the machine.

Tom

 

[Bob Carnie]

Tom
I think this is where the problem is.
We have a separate graduate with wetting agent in distilled water off to the side and all film is gently dipped and drained before going into the dryer.
I believe this is the foaming of wetting agent on your film.
You may be able to wash this off if it is on the base side, if it is on the emulsion then most difficult
Bob

Bruce,

Thank you for your response. I have been using the wetting agent bath off the Jobo but within the tank, and with the film still loaded on the reels. As my unit is the ATL-2300 the solution timing is automatically handled by the machine.

Tom

 

[Tom Kershaw]

I've now made contact sheets of four rolls of Delta 400 processed as a test after soaking and rinsing the tank and reels in warm water; the bubble marks are still visible on one frame of one film, but to a lesser extent than my initial examples. I processed the film with four reels in the tank (no blank reel), so the next step may be to process a batch of films with the fifth empty reel in the tank. It is possible that the presence or otherwise of the fifth reel may alter solution flow and increase the probability of the bubbles.

Tom

 

[DanielStone]

I think it has to do with the developer.
I have seen it before, as in this photograph of mine, developed in a lab where the whole negative had this band of bubbles:

I am not sure causes it exactly though.

to be totally honest, this looks really cool . though i'm sure its not what you originally intended

-dan

 

[Tom Kershaw]

How quickly can Pyrocat-HD fail? I made up my solution on February 6, 2009, decanted into 250ml containers. As I now seem to be having problems with very low densities perhaps it is time to open up some fresh solution...

Tom.

 

[Tom Kershaw]

Update: Using fresh solutions (unopened since mixing on 2009/2/6) and being concerned with keeping the wetting agent off the Jobo reels seems to have solved this problem. I'm still using a 2 minute pre-soak as no pre-soak produced odd results in terms of contrast.

Process sequence:

• 
  50 r.p.m
  2 minute pre-soak
  8 minutes development at 24.5ºC (Jobo reports 24.5ºC as 26ºC)
  1 minute acid stop bath
  1 minute wash
  5 minutes fix
  2 minutes wash
  external wash
  external from Jobo tank wetting agent step.

Tom

 

[Ronald Moravec]

I presoak is only necessary with hand agitated sheet film to stop sticking. No film manufacturer except EFke says to use a presoak and never did for last 50 years and Ilford specifically recommends against it.

Make sure you use the center tube or funnel so the tank fills from the bottom up in a uniform mannner. For Jobo, keep the speed up full for 60 sec during and after developer is introduced.

Keep wetting agents away from plastic reels and fully wash after use.