C-41 Development weird streaks. Is this bromide drag and if so how to fix it.

The agitation of rotating in one direction was mentioned. Imagining that in my mind, turning in the same direction, could it be that the spiral of the film is acting like a water pump, and the pressure of the water might be pushing the film from to touch the piece of film just outside it on the spiral? I don't know if I am explaining that right. I also wonder if color film "softer/more flexible" when wet than b/w film? And so the color film being flexed so it touches the next piece of film on the spiral?

My very first development tank was a Yankee. I bought this back in high school in the late 70's. It has a combination thermometer / real agitator. I remember one time I was agitating film, and I was only turning it in one direction (not back and forth as recommended), and when I finished the film and took off the lid, my film had actually unspooled off the real. I know your film didn't go to this extreme, but I wonder about film flex and if the real was being turned, so the outer end of the film was constantly "pulling" developer from the outside to the inside as it turns and this force of "pumping/moving" developer puts pressure on the film flexing it. But what you/I can envision in your "mind's eye" certainly doesn't necessarily mean it is happening in the real world!

ludwighagelstein said:

No, it is persistent throughout the whole roll, on about 50% of the frames, exclusively in the highlights. Thats the thing. It is definitely a chemical issue, but I don´t know which one. Bromide drag seems obvious, but the agitation should have been more than sufficient to avoid such issues. The film looks impeccable, is absolutely flat, has no knuckles. I take great care in my processing, even with the rudimentary processing equipment I use I´m able to keep the temperature constant within a 0.2 to 0.3 °C margin along with constant rotary agitation. The chemistry was fresh. I don´t know what could have caused this issue.

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how long does the film sit in the tank until the screwdriver rotation starts?

RalphLambrecht said:

how long does the film sit in the tank until the screwdriver rotation starts?

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and do you do a pre-soak?

RalphLambrecht said:

and do you do a pre-soak?

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I do 5 mins pre-soak at 38°C then I pour out the soak and pour in the developer. Agitation starts when the developer is fully poured into the tank

You need more data. How many rolls of C41 have you processed this way? Try your setup without the drill ,just use the Paterson agitation stick. Back and forth.

mshchem said:

You need more data. How many rolls of C41 have you processed this way? Try your setup without the drill ,just use the Paterson agitation stick. Back and forth.

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The thing is, I have developed more than 25 35mm Rolls and about 10 120 Rolls of colour film with this agitation method and this problem did never occur. The Paterson agitation stick is attached to the drill. The agitation device I built myself is quite handy though, because I often do push developments of 4 to 5 stops with Fuji CDU2 in C41, and if the developer has seen a few rolls already the dev and blix times get exceedingly long, thats my reasoning for automated agitation in the first place.

And that last post makes chemical / process problems more likely than bromide drag / agitation.

PE

Photo Engineer said:

And that last post makes chemical / process problems more likely than bromide drag / agitation.

PE

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I´ll develop another Roll of Film in the same batch of chemistry with the same process. If the problem is not persistent, then I´ll just have to live with the risk of ruining a film once in a while ?

Or agitate as shown in the Kodak illustrations, or by another proven method.

PE

If you are processing a lot of film, I would buy a (if you want to use Paterson) deep tank, and incorporate into your temp. control set up. If you use Kodak Flexicolor RA C-41 chemisty you can replenish. The drill agitation is too much, IMHO. Flexicolor RA C-41 has separate bleach, and fixer. Because this is designed to be used in a high speed minilab, you only need to stand and agitate for 7 1/2 minutes, not even that really. The bleach takes 1 minute, and the fixer takes 1 minute. A 5 liter batch of Flexicolor will last a very long time if cared for in a seasoned "tank", and properly stored in full bottles. 1ea. 5L bottle of bleach will last forever, once you make up your working solution it takes something like 9mL ?? per 80 sq. in. to replenish. You will go through the developer and fixer at a faster rate.

IMHO, you need chemistry that has the same activity, more or less, for each roll. The overused Blix, instead of separate fresh Bleach and Fixer, will give you nothing but headaches.

I've used the Tetenal kits, they work OK, as long as you don't try to overuse them. I'm of the opinion, if I am buying Professional films, I will use professional chemistry. Fuji for E-6, Kodak or Fuji for C-41. Tetenal is an outstanding company with great products, Kodak Alaris and Ilford get (AFAIK) all their powdered, and liquid black and white chemistry from them. The Kodak color chemistry for the US is made by Kodak Alaris (China). Fuji-Hunt have plants in the Netherlands and the US.

If you are going to agitate the way you are going to need to keep your chemistry fresh. You may be aerating/oxidizing the solutions??

I have, among every other tank known to man, a 8 reel Paterson tank, deep 8 reel SS tanks etc. It's a simple matter to develop 8 rolls of 135 at a time, and replenish the chemistry.

Mike

Did you figure out your issue? Was it exhausted blix?

Hello,

I have a similar problem so I thought instead of opening new thread I can ask here.
The issue is grey bars repeating through whole roll of film. It is not cause by scanner as i can see it on the film itself and it show on darkroom prints as well.
Kodak Portra 400 120 pushed 3 stops
developed in Tetenal Colortec C-41 kit, fresh mixed working solutions, development time 4:45 (3:15 is standard plus 30sec. for each stop push), Bleach Fix 4 minutes, Stabiliser 1 minute. No pre rinse
I have recently bought the Job processor hoping that it make the processing more easier and consistent and this is my first film developed. Before I was developing in Paterson tank and agitated with the stick provided. I tried few test rolls after and never experienced the same problem but would like to find out why this happed so I know what to avoid in the future.
I will very appreciate your advices.
This is my first post here, but I already found lot of useful tips here in the past.
Thank you

Ps: pleas excuse the poor scan quality, I tried to emphasize the bars.

Cannot tell due to obstruction.

PE

Looks like something produced by the camera or the developing reel.

When first posted I was distracted by the background banding. On second-look, I think it is the horizontal bar near the bottom of the picture. If that is is, it might be a bit too well defined and straight to be a chemical artifact.