Uneven development of FP4 in XTOL in JOBO 3010

[Grumium]

Hi all,

I have developed a few hundred rolls of 135 and 120 without any issues (except for those that where messed up by the operator ^^) and now that I am shooting 4x5 I am confronted with uneven development (read: uneven development and signs of foam bubbles). I use a Jobo CPP3 processor and develop FP4 in a Jobo 3010.

This is my process:

1) Pre-Wash

5 minutes @ 20°C
Distilled water

2) Development

7 minutes (N-1) @ 20°C
Kodak XTOL 1+3, 1000 cc.
Fresh mix (with distilled water)
Drum speed 50 rpm

3) Stop bath

2x 30 seconds @ 20°C (± 1°C)
Tap water (water hardness: 16 °dH, CaCO3 285 ppm)

4) Fixer

Two bath fixing with Moersch AKS alkaline
2x 2 minutes @ 20°C
Mixed with distilled water

5) Final wash

Tap water (Inglis film washer)
15-20 minutes @ 20°C (± 1°C)

6) Rinse

Rollei Wetting Agent 1+5000
1 minute @ 20°C (± 2°C)
Distilled water
(Photo Flo and Jobo 3010 are strictly separated thus no contamination)

Example 1: Foam marks on the left.

I have noticed before that XTOL is prone to foaming but have never detected an impact on the negatives. This is still the case for 135 and 120.

In my opinion the uneven development takes place between the development step and the stop bath. Draining takes about 12 seconds, full refill about 10 seconds (drum turning again). Developer bubbles that sit on the film surface could continue development locally. What do you think?

Please note that the uneven development and bubble marks are almost not visible to the naked eye when viewing the negative. A steep curve (see below) after scanning helps. It's still visible when applying a gentle curve.



Advice is highly appreciated. Is there anything that can be added to the developer to prevent the build-up of foam?

Please find more examples (exaggerated curves only) in the next post.

[Grumium]

Example 2: Foam and running marks on the left.


Example 3: Foam marks on the top border.


Example 4: Vertical streaks (in drum rotation direction).

Please note that the left side went always into the Jobo 3010 first.

[vinny]

are you leaving the edge of the film flush with the drum or pushing it all the way in?
How I do it: I only pre-rinse for 3 min max.
I don't use more than 500ml in the 3010 drum. If you insist on using 1L at a time, split it up and use 1/2 for the first half of development, then the other half for the remaining time.
I use water stop bath. Stop bath shouldn't be causing you issues though.
I don't push the film past the edge of the drum.

[Michael R]

I've never used a Jobo so this may or may not help, but I use a lot of XTOL (never had foaming issues), and know of several people who do use Jobo expert drums with XTOL and have no problems, so there is probably a solution, or several solutions to the problems you're having. Unfortunately when there are multiple steps and variables involved, diagnosing and solving sometimes comes down to experimentation. I will offer some general ideas with respect to development uniformity, streaking and foaming artifacts:

1. While I believe Jobo recommends pre-soaking, with some films (including Ilford's) a pre-soak can sometimes cause uniformity and foaming issues. Some emulsions seem to incorporate surfactants to help promote more even wetting and uniformity. Ilford does.

2. Regarding uniformity and/or streaking, try a standard acid stop bath vs the water rinse after development in this sort of situation. You can still do a water rinse after the stop bath if your alkaline fixer is not buffered for use with acid stop baths.

3. Maybe 1000ml is just too much solution (even though Jobo says it is ok, maybe better to back off the max. recommended volume).

4. Perhaps agitation is not vigorous enough (relates to solution volume and rotation speed - see #3 above)

[Ari]

Agree with the others: too much developing solution is a likely cause.
Jobo recommends about half that amount with the 3010, maybe less.

Ilford doesn't recommend pre-soak, but like you, I do it anyway.
Where I differ is I pre-soak twice, for 1 minute each time.
If I'm in a hurry, I'll pre-soak once for 1 minute, works just fine.

[karl french]

1 liter of chemistry is fine in a 3010 drum.
Do NOT use a pre-soak/wash with Xtol.
Kodak recommends 100ml of stock solution per roll, you have that covered with 250ml of stock to 750ml of water. Though the constant agitation of rotary processing might exhaust the developer faster.
Why 1+3? Why not 1+1? 250ml stock + 250ml of water will work just fine.

I agree Xtol is prone to foaming, but I've never seen such results on my film.

[Bruce Watson]

In my opinion the uneven development takes place between the development step and the stop bath. Draining takes about 12 seconds, full refill about 10 seconds (drum turning again). Developer bubbles that sit on the film surface could continue development locally. What do you think?

Unlikely. The last few seconds of development are the least critical. This looks like what I'd expect from the first few seconds of development which are very critical.

My guess is that the prewash with the FP4's surfactants and the high rotation speed of the drum all combined to make foam. Then when you poured in the developer, the foam prevented the required quick and even immersion of the film in the developer.

What to do? First, stop using a prewash; not recommended with XTOL. Second, slow the drum to 30 rpm. Third, lengthen your development time to compensate for the slower drum speed and therefore the lesser agitation (I'm guessing somewhere around 8 to 8.5 minutes maybe, but test to find out exactly).

I've been using XTOL 1:3 in a 3010 drum (1 ltr) on TMY-2 for years without problems. It can certainly be done, I've put more sheets than I can count through my CPP-2 and 3010 drum. Nothing but perfect results, nothing but perfectly graded silky-smooth skies.

[Kodachrome25]

I have never had issues with running film in my 3010 but I really appreciate the trouble shooting tips brought forth in this thread. The only thing better than good working knowledge is even better working knowledge.

[Grumium]

I would like to thank you for your responses and echo the conclusion of Kodachrome25: The tips and your efforts are highly appreciated.

Unfortunately I won't be able to perform further testing within the next weeks but I will keep you posted about my progress along the way. It may help others in the future.

I started to make a root cause analysis (control freak) in order to narrow down the potential causes and took your tips and thoughts into consideration.

(1) Alignment of sheet
Vinny: You pointed to the positioning of the sheets. I don't push them hard against the bottom but try to top-align them with the circumferential joint-line of barrel and top-cover (see #4). Please find sketches of the different possibilites below. How do you do it?



(2) Leveling
Although I did neither level the processor nor the drum I rule a leveling issue out. First, the base is rock solid and virtually level. Second, I used quite a lot developer thus it should have covered the whole area of the film at any time.

(3) Pre-Wash
I opted for a pre-wash primarily in order to overcome short development times. The pre-wash gave me roughly another minute of development time. As you can see in my first post development time for N-1 is quite short (it was way too short for N-2 and without the pre-wash). As Jobo still recommends it I did not anticipate an adverse effect on iamge quality. I may be wrong and will test development without it next time (Test 1).

(4) Dilution
I do use 1+3 because of the same reason as I did implement the pre-wash: Development time. I'd really like to do 1+1 as I do for all my 135 and 120 but development times of 5 minutes and less are not acceptable.

(5) Speed
As far as I remember Jobo recommends a speed of 65 rpm. I didn't find a hint saying that a slower (or faster) speed leads to more uniform results. I will check the effect of low (Test 2) and high (Test 3) rpm next time. Bruce: Thank you for indicating that lower rpm will increase development time (this may be very helpful).

Edit: In case you haven't seen it before, Catlab presents a demo model of the said drum on Youtube: https://www.youtube.com/watch?v=ZCUSWwse1M4

(6) Stop bath
I do use a water bath only in order to not acidify the alkaline fixer and to keep things as simple as possible. As Michael suggested I could do an additional rinse to overcome this risk and will do so if all the other countermeasures don't pay out (I do hope that the issue is really caused in the first seconds of the development as Bruce presumed).

(7) Volume
Due to the dilution (1+3) and the required minimum amount of full strength developer (250 ml for 10 4x5) I end up with 1000 ml. What's the rationale for recommending to use less volume? The motor of the CPP3 can handle it easily. Draining time won't make a big difference. Foaming behaviour should be independent of the volume?

[Grumium]

I would also like to share my development times for the process as given in the first post (as I already referenced to those a few times above). Please note that I develop to N-1 mainly.

Zone development | Time mm:ss | Film speed ISO log (to be rounded)
N-3 | 06:00 | 16.5
N-2 | 06:30 | 17
N-1 | 07:00 | 17.5
N | 08:30 | 18
N+1 | 11:00 | 19
N+2 | 16:00 | 20
N+3 | 25:00 | 21

In addition to (1) of my previous post I attached an image showing #4 in more detail.