Tetenal c41 troubleshooting + general questions

[Photo Engineer]

Well, bad pouring can be jerky or interrupted. It can be slow then fast or fast then slow. There are many ways.

Agitation can involve RPMs that are too low and which then lead to uneven spread of chemicals.

That is why I recommend a prewet. It will dampen out some of this.

PE

 

[morback]

Update time!

I got rid of the bubbles. Turns out lowering the agitation to one speed above lowest got rid of that problem.

Now that this is out of the way, my medium format still shows issues: yellow fogging and some uneven development "streaks."

I will follow your suggestions for those, starting with stop bath.


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[Photo Engineer]

You have to insure somehow, that that level of agitation gives the right image quality. If it is too low, the images will be low in contrast and may have crossover.

PE

 

[morback]

Well, I cried victory too early. Here are the results of the last processed batch.

Method:
2x30s pre-wash (at 38C)
3:45 dev time (as per instructions, 3rd re-use)
00:30 stop bath (1:9 from Kodak)
1:00 water wash
14:00 blix (I add time)
the rest as usual...

I seem to have gotten rid of the uneven development but my bubbles are still here:

Now I identify 3 issues:
1) bubbles
2) yellow fog/oxidation
3) something is happening on the edge of my negatives (related to #2?)

It's worth noting that I could only find the bubbles on 1 frame per film (I washed 4 at once). My test medium format seems quite clean except for the "road ruts" (as someone else called them) and a darkening of the right edge which might be scanner related (as in the 35mm examples, if you see a black edge by the frame, the corresponding brown burning on the frame is due to the scanner light leaking through).

I was going to try the alternative process as I see no other alternatives left (except getting my hands on a digibase kit), but after reading through the posts, it doesn't seem worth it. Though these posts were usually lacking visual examples.

What to do now?
m.

 

[Photo Engineer]

Did you notice that the marks are roughly "H" shaped and are in roughly the same place on every picture? Since you call these screen shots, I have to assume that those defects are due to reflection from the screen, otherwise they are some sort of light leak. IDK.

Compare 1, 2 and 3 for "H" shape in upper left and 4 and 5 for a line in the lower right. These are dark in the negative and thus could even be light leak in the camera due to the repetitive nature if from different frames.

Please clarify the source of the images more.

PE

 

[morback]

Hi PE,

These are screenshots, but not taking with a camera off the screen

As for light leaks: these are from 3 cameras. One Rolleiflex and two Leica M. The negatives show absolutely no indication of light leak. As I said earlier, these things are impossible to see with the naked eye.

Also there are only three pictures: a processed and not processed for the 35mm and a processed for medium format.

I noticed I posted one in double, I will try to remove it.

m.



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[Photo Engineer]

This is very odd as the defects I see there do not look like process faults.

PE

 

[morback]

Hmm, looks like I exhausted this forum. Do you have a recommendation for a knowledgeable German and a French forum where I may present my issues again?

APHOG.de is not accepting my gmail address...


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[gzhuang]

2 Cents Worth

Since I began developing my own negatives, I've been using the rotary tube processing method though I'm using a hand tank.

Pre-Soak - Rinse 2 times

Developer - 17.5min/75F or 14.25min/80F

Rinse 2 times

Blix - 8 minutes (75F/80F)

Rinse 4 times

Stabilizer - 1 min (80F)

Rinse & Dry

+1 add 1.25x developer time. +2 add 1.5x developer time.

So far so good.

 

[zehner21]

Since I began developing my own negatives, I've been using the rotary tube processing method though I'm using a hand tank.

Does it mean that you roll your tank on a plane? If so, how much solution do you pour in it?

 

[Photo Engineer]

Since the defects have a distinct pattern, it is hard to see how they arose by processing. Usually, process defects are ill defined except for bromide drag. If it is bromide drag, it is an agitation problem.

PE

 

[morback]

I have trouble to see how 5 cameras could suddenly produce these effects on their own. I'm very sure it's a processing issue.

Agitation. Let's work with that. I used the highest speed, the recommended "p" speed and now "4" which is almost the lowest speed.

It seems that the lower I go, the less pronounced these effects are. I also read a German post saying he was actually using the slowest speed. I couldn't bring myself to do that yet, but what choice is left?

I'm also considering my pouring. I used to fill the lift's little cup and let it guzzle down (noisily). Last time I tried to pour without accumulation. But still got those things...


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[Photo Engineer]

Lets look at two images here:





Do you see the "H" in the one with the crane almost pointing to the bar in the "H" which is at an angle to the frame? In the other photo, in the lower right, do you see the regular bar with sharp edges at an angle?

These are very difficult to get my means of processing except by bromide drag through sprocket holes or by a spill of liquid, but in the latter case, the spill generally has a head and tail.

So, this might be light fog as you load the film.

These differ from those in the OP as well.

PE

 

[Photo Engineer]

Remember that lower speed gives lower contrast, and that makes the defect less noticeable.

As for the defects, if it is fog then film from 5 cameras can show it if it is a light leak that is consistent with the placement of film or reels in the darkroom or if it is due to a defect in the reel or equipment itself.

I have a hard time reconciling that "H" shape with agitation, but I can see it with fog through sprocket holes.

PE

 

[gzhuang]

Does it mean that you roll your tank on a plane? If so, how much solution do you pour in it?

Using a Paterson 4 on a dental shaker for agitation. Standard 500ml for a 2 reel tank.

 

[morback]

Just found these images, trying to check your hypothesis:

A "normal" one, no visible defects I can see (except this yellowness)

And now one with something I've never noticed before: an airbell (next to what you assume are light fogging)

does it help narrow a diagnostic?

 

[Sirius Glass]

The second one may not have been put in the developer evenly [all at one time].

 

[Photo Engineer]

On the pictures that I reposted, I suggested light fog due to regularity or bromide drag. These latest samples look entirely different, but the top picture is definitely suggestive of bromide drag and the bottom picture is suggestive of uneven wetting with water before development or uneven coverage with developer when you pour it it.

These two sets do not look like they can be equated. There is some mismatch here to me.

PE

 

[p_antonov]

Hi

I am wondering if you managed to resolve this issue in the end.

I seem to have similar issues with large format negatives developed by a lab using Jobo rotary processor, and the lab technicians do not seem to have a solution so far.

The negatives come out with foam / bubble-like patterns mostly visible in the lighter areas of the negative, especially along the longer side and with what looks like flow streaks across the shorter dimension. There are also steps in density with pronounced diagonal edges. The attached examples have digitally increased contrast but you can see the defects on on normal scans. They do not pop out straight away, but you have no problem finding them once you know that they are there.

 

[Photo Engineer]

This looks like they used too little solution, too slow a rotation or may need a stop bath. All three of these can cause similar problems alone or together.

PE

 

[klownshed]

I have had the foam bubble issue before.

I think it may have been related to using stabiliser in the tank, and it not quite being washed enough after use and foams up the next time the tank/reel is used.

I have stopped using stabiliser in the tank now, I take the film off the roll and use the stab in a different container.

I've not seen the bubbles since.

But that might be just down to coincidence. I'm no expert and am expecting somebody far more knowledgable to say why it's not the stabiliser... ;-)

Edit: Didn't see PE's reply above. I haven't used a stop bath with C-41 so that could be a reason. My Jobo has one speed so there's nothing I can do about that! ;-)

 

[p_antonov]

Photo Engineer, klownshed, thanks!

What would be the way for the insufficient solution volume to cause it? The foam is mostly along the longer edge of the sheet, which should be vertical during the development, so I would expect that the rotation should take care of that?

I do not think they are using stop bath, but I will see if they can start using it. I understand it is not a compulsory step in C-41 development?

Is there a speed setting that you would recommend to avoid this, or is it more trial and error? I will check what speed they use.

My first thought was of the tank / reel being contaminated with surfactant as I had had a similar issue with my home B&W development. The lab technician however dismissed the suggestion, as the tank is constantly rotating unlike with home B&W.

Also, can it be the case that the next solution is not poured in quickly enough after the developer is out of the tank and the remainder is left foaming on the surface? I.e. a combination of stabiliser contamination + slow speed + lack of stop bath?

 

[Photo Engineer]

Insufficient volume leads to "sloshing" or "churning" of the developer causing a sort of foaming action. This causes bubbles. It also causes streaks due to slow coverage of solution. A prewet can help greatly in fixing this if they think the volume and speed are ok.

This is most likely.

Speed can be helped by going up one step and see if it helps.

A stop bath would only be a last resort if all else fails such as more volume and faster pouring.

I have never ever seen surfactant cause this, but then I wash my tanks and reels very well with hot water.

PE

 

[p_antonov]

Thanks a lot. I will talk to the lab people and see what they have to say. Pre-wetting was too a suggestion from someone with whom I discussed the issue earlier.

 

[blockend]

I have had the foam bubble issue before.

I think it may have been related to using stabiliser in the tank, and it not quite being washed enough after use and foams up the next time the tank/reel is used.

My first thought was soapy contamination at the development stage. Detergent residue from washing but not rinsing, or stabiliser in the tank from previous use. I've hand processed literally hundreds of C41 films in Tetenal and never had any symptoms like the OP. No special care or pre- or post- washing, just follow instructions, use a twiddle stick not inversion, and concertina tanks. I abandon the chemistry at 25 films (mixed 35mm and 120) with no discernible colour shifts, and have tried more in the past.