Strange, subtle bars of color on negatives...why? (example inside)

moodlover · Aug 14, 2015

My color scans have strange bars of color that shouldn't be there. Here is an example:

Kodak Portra 400 (120)
Jobo C-41 1L press kit inside 500ml Paterson tank
Processing:
1. Pre-soak in 38C/102F water for 3 min
2. Develop at 102F for 3.5min, first 10s reel spin agitation then 4 inversions every 30s
3. Blix at 102F for 6.5min, same agitation as above
4. Wash at 102F for 3min
5. Stabilizer at room temp for 1.5min (agitate first 15s)
6. Hang dry for 2 hours, cut, scan on Epson V800

Theres an orange bar under her arms, a gray one going down the side of her face, then the large blue blob of color at the bottom left. Does anyone know why this happens and how I can remedy this? I thought they might be light leaks but that wouldn't explain the gray bar going down from her face to chest...

DWThomas · Aug 14, 2015

The fact that the bars appear to have straight well defined edges might suggest a scanning/dig@l handling problem or else perhaps some sort of subtle light leak involving space outside the camera film gate.

(But that's a wild guess on my part.)

moodlover · Aug 14, 2015

Here's a closeup from another frame where the bars get wavy:

DWThomas · Aug 14, 2015

AH -- that looks more like possibly an uneven distribution of chemistry -- maybe not enough in the tank or ?

moodlover · Aug 14, 2015

Yes thats what I was thinking at first, but then remembered I fill the tank until I can see the chemistry come out from the top of the entry point so I know its more than full.

I dont think its my scanner (which is brand new) since I develop b&w in D-76 with flawless scans. Some of my C-41 frames are perfect as well so this is really a frame to frame issue (which makes me think its a chemistry problem).

Rudeofus · Aug 14, 2015

I was thinking about improperly film tank at first look, but that gray bar in her face goes perpendicular to any possible fill line. Only question remaining is how quickly you fill your tank. C-41 is a fast process, and 0:30 extra dev time in some area means a local push by a full stop.

moodlover · Aug 14, 2015

I take about 10-15 seconds to fill the tank with developer, put the agitation stick in, THEN start the timer for 3:30, is that too long? I'm not sure how I'd make it faster

garysamson · Aug 14, 2015

You should be inverting the tank for agitation, and NOT using the stick to spun the reel, throw it out!

moodlover · Aug 14, 2015

Hmm, thats what I prefer to do cause the stick is hard to get positioned sometimes. Though the instructions in my kit said to "Agitate continuously for 10 seconds then 4 inversions every 30 seconds afterwards. So I take "agitate continuously" to mean spin the reel, and "inversion" to mean flip upside down.

Xmas · Aug 14, 2015

Rescan all these examples upside down or emulsion out.

Sirius Glass · Aug 14, 2015

Not enough chemistry in the tank. Period.

AgX · Aug 15, 2015

moodlover said:
Yes thats what I was thinking at first, but then remembered I fill the tank until I can see the chemistry come out from the top of the entry point so I know its more than full.

A completely filled tank will not allow agitation by inversion.

moodlover said:
Hmm, thats what I prefer to do cause the stick is hard to get positioned sometimes. Though the instructions in my kit said to "Agitate continuously for 10 seconds then 4 inversions every 30 seconds afterwards. So I take "agitate continuously" to mean spin the reel, and "inversion" to mean flip upside down.

Likely "agitation" too refers to flipping of the tank. (But I never used any Paterson tank, did not even know of that stick.)

pdeeh · Aug 15, 2015

The development time for C-41 is 3 minutes and 15 seconds - any particular reason why you are developing for 3m30s ?

Xmas · Aug 15, 2015

AgX said:
A completely filled tank will not allow agitation by inversion.
Likely "agitation" too refers to flipping of the tank. (But I never used any Paterson tank, did not even know of that stick.)

Both points true. But you can swizzle
Patterson's have quantities on base of tank you need to measure in graduated vessel or fill to base of funnel. The air space is needed for flow. They were even at one time supplied with clips to stop reels from moving...

But the OP needs to rescan these might not be chemistry artifice.

moodlover · Aug 15, 2015

AgX said:
A completely filled tank will not allow agitation by inversion.

I didn't say completely filled to the brim, I said above the entry point (so I can see chemistry filled up above the hole of where its poured in, I know the entire roll's area is covered).

AgX said:
Likely "agitation" too refers to flipping of the tank. (But I never used any Paterson tank, did not even know of that stick.)

Right but it also uses the word "inversions" separately.

pdeeh said:
The development time for C-41 is 3 minutes and 15 seconds - any particular reason why you are developing for 3m30s ?

I think it's different for certain brands. The Jobo C-41's instructions state 3m30s.

franck · Aug 15, 2015

Hello,

My guess would also be some form of uneven chemistry problem.
In such a case, the Tetenal c-41 kit I am using recommends to develop at 30°C instead of 38°C.
I have not compared the two directly but I am only developing at 30°C both in a Paterson tank with 3 inversions every minute and in a Jobo rotary processor.
Both have given me very consistent results. 30°C is easier to maintain with good precision and the longer times are easier to get consistent.

Cheers,

Franck

Mark Antony · Aug 15, 2015

moodlover said:
Here's a closeup from another frame where the bars get wavy:

I think I know what has happened here. I think your initial agitation with the stick has caused a meniscus on the top of the solution by centrifugal force. If this is correct the inner top edge will be worse than the outer (when viewed in the spiral). I process 120 in the same tank as you and as far as I can see you have the same modus as I do except I don't use the twizzle stick.
I pour in the solution then start the timer after I place the lid on and give slow agitation for the first 30 seconds when I give two sharp taps and crack the pressure of by lifting the lid.

Try putting the spiral in the tank with the same amount of solution (water) leaving off the clip in funnel. Now try agitating with the stick and you will see the effect I mention above where the inner part of the spiral is covered with less solution than the outer.

If you want to use the stick you might need 50ml more solution to cover.

Jim Noel · Aug 15, 2015

"Agitate continuously" has nothing to do with the method. Inversions are the only adequate method of agitation in a tank.

lhalcong · Aug 15, 2015

To me, the waves in that last pic resemble the waves of a liquid, which makes me incline towards chemical problem. But you have three different issues here and possibly not related to each other. For instance the blue blotch of color only on one corner would make someone think there was some light leak at some point during the whole process. and the straight gray line going vertical resembles a scanning issue. But I can't simply assure I am in the right track. They are ideas that can be proven by further tests . For once , correct your agitation as recommended, make sure there are absolutely no accidental light leaks anywhere from camera to process. and test your scanner , sometimes it may just be an isolated scanning issue that goes away or reoccurs when the conditions are met.

Sirius Glass · Aug 15, 2015

Sirius Glass said:
Not enough chemistry in the tank. Period.

As an example:

moodlover said:
I didn't say completely filled to the brim, I said above the entry point (so I can see chemistry filled up above the hole of where its poured in, I know the entire roll's area is covered).

I use the Jobo tank recommendation for using the Jobo processor which is usually 05. liters

Peltigera · Aug 15, 2015

If you do use the stick to agitate the solutions, it is important to twist the stick both clockwise and anti-clockwise. You need to produce turbulence in the liquid and twisting in one direction does not do this. Inversions are better - and the liquid fill should be measured: the Paterson tank has embossed on the base how much liquid to use to cover a 120 reel. Use this much, there is no benefit to using more.

Sirius Glass · Aug 15, 2015

Peltigera said:
If you do use the stick to agitate the solutions, it is important to twist the stick both clockwise and anti-clockwise. You need to produce turbulence in the liquid and twisting in one direction does not do this. Inversions are better - and the liquid fill should be measured: the Paterson tank has embossed on the base how much liquid to use to cover a 120 reel. Use this much, there is no benefit to using more.

The Jobo processor is even better and pays for itself quickly because you will avoid other problems.

ianp · Aug 30, 2015

FWIW when I first moved from stainless steel reels and tank to Paterson I started to get surge marks on the negatives just down from the sprocket holes. This occurred on some but not all exposures. Someone mentioned that with a Paterson tank it should be a rolling/twisting rather than an inversion type of agitation. I moved to that and the issue disappeared.

See here

[video]https://youtu.be/yW0gt-6zGnw?t=315[/video]

Sirius Glass · Aug 30, 2015

Sirius Glass said:
As an example:

I use the Jobo tank recommendation for using the Jobo processor which is usually 05. liters

That should be 0.5 liters not 05. liters.

MattKing · Aug 30, 2015

ianp said:
FWIW when I first moved from stainless steel reels and tank to Paterson I started to get surge marks on the negatives just down from the sprocket holes. This occurred on some but not all exposures. Someone mentioned that with a Paterson tank it should be a rolling/twisting rather than an inversion type of agitation. I moved to that and the issue disappeared.

See here

[video]https://youtu.be/yW0gt-6zGnw?t=315[/video]

You should note that the tanks pictured in that video clip are the older style of Paterson tanks,.

I use a combination of inversion and twist, and try to make sure that the developer "tumbles" through the film reel.

Strange, subtle bars of color on negatives...why? (example inside)

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