Ilford FP4+ or Delta 100: "moon crater" pattern on skies after a long exposure

[alps-art.ch]

Hi all,

i have a problem developing 4x5 Ilford FP4+ or Delta 100. I developed using Jobo CPP2 in 3010 drum with developers like Pyrocat HD or Adolux. While at ordinary exposures like 1 sec my negative have no problems, both films show a "moon crater" pattern on even areas like sky after a long exposures (like 1 min) through a dense filter. Perhaps i overexposure them a bit. The pattern, though relatively low-contrast, is still noticeable on optical prints. Attached are a couple of over-contrasted crops from two images (one is horizontal, another is vertical)

155767 155768

does anybody ever seen this?
thanks a lot for your suggestions..

Dimitri.

[Jac@stafford.net]

Are you pre-soaking the film in water?

[Kevin Harding]

I have no idea the cause or the relation to long exposures, but those look like bubbles or foam to me.

[Willie]

Any place you could have gotten condensation on the film before or after you exposed it?

[Jim Michael]

I have no idea the cause or the relation to long exposures, but those look like bubbles or foam to me.

Yeah that looks like bubbles from a strong photo flo prewash.

[Mark Sampson]

I can't see where exposure time could cause this. It does look like condensation or, perhaps, too much in-process agitation without sufficient chemistry. Which could possibly cause the 'foam' effect. I'd run another test to see if you can replicate it.

[williaty]

That's 100% certain to be foam in the developer. I've fought that stuff twice over the years. Helped a fellow on another photo forum diagnose and resolve it just a couple of months ago. Here's an example of my recent problem. You can even see how the foam is on one side of the roll (top in this picture) but goes away towards the bottom where the film is low enough to be setting in fully liquid developer.

https://c2.staticflickr.com/8/7566/27539374096_02c6aeb8ce_b.jpg

[alps-art.ch]

Are you pre-soaking the film in water?
I don't


Any place you could have gotten condensation on the film before or after you exposed it?
well, i keep film in food fridge before and after exposing, not sure if this cause severe condensation. I guess not as ambient temperature and humidity in Switzerland is not high.


.... I'd run another test to see if you can replicate it.
It is reproducible, unfortunately... I have quite a number of good negatives spoiled with this.


That's 100% certain to be foam in the developer. I've fought that stuff twice over the years. Helped a fellow on another photo forum diagnose and resolve it just a couple of months ago. Here's an example of my recent problem. You can even see how the foam is on one side of the roll (top in this picture) but goes away towards the bottom where the film is low enough to be setting in fully liquid developer.

https://c2.staticflickr.com/8/7566/27539374096_02c6aeb8ce_b.jpg

True, looks very similar... True also that I often observe residual foam on drum lid after processing. Any suggestion then how to reduce foam in developer? Use another one? Add a foam-calming agent?

BTW, I also observed foam on tank lid when I develop films with D-76, but never had this problem on negatives. Perhaps, smaller quantity of developer (250ml) helps? With 250 ml I can use bidirectional rotation, while with 1/2 litre of Pyrocat HD or Adolux it is not possible, as too much inertia might destroy drum fixation.

thanks a lot alredy for your replies, guys!!

[IanG]

You need to clean the tank etc well with reasonably hot water, you must have a severe build up of wetting agent on the reels etc. It should be impossible to get foaming with Pyrocat HD if everything is properly cleaned after use.

Ian

[Leigh]

In well over 50 years of processing film I've never once seen foam in the developer.
I don't even know what might cause it.

Do you wash your tank thoroughly after each processing cycle, after the film is hung up to dry?

It's possible you have residual photo-flo in the tank when you start processing the next roll.
That would certainly cause bubbles, since photo-flo is soap.

=====

I would not recommend refrigerating film after it's been exposed.
New film is sealed with an inert gas having very low water content.
Once the package is opened, ambient humidity will be present.

- Leigh

[alps-art.ch]

I googled a bit for "foam 3010 drum" and apparently people were in same problem:
http://www.largeformatphotography.info/forum/archive/index.php/t-116560.html

the one before the last reply just answers my question!

I also found an image with same nasty bubble pattern: http://www.apug.org/forum/index.php?threads/recommended-usage-development-recipes-for-jobo-3010-drum-a-besler-motor-base.50783/. interesting that foam leaves traces on overexposed areas. It is understandable, as at lower density areas entire latent density is revealed during development, while bubble edges, stuck constantly at high density areas, cause over-development underneath.

[IanG]

There are surfactants in some film and paper emulsions these aid coating and also help during development. I've seen them build up in the print developer tray and they will withreplenished film development but won't normally cause an issue.

Ian

[alps-art.ch]

@IanG & Leigh: Yes, thanks, I will clean my drum thoroughly.

[Willie]

While at ordinary exposures like 1 sec my negative have no problems, both films show a "moon crater" pattern on even areas like sky after a long exposures (like 1 min) through a dense filter.

Have you tried a different Neutral Density or other 'dense filter'?

If this problem is only with negatives through your dense filter that is where to start. I did not pick up on this the first go-round. Shorter exposures are no problem. Longer exposures through the filter are. Try a lower light long exposure with a sheet of film with no "dense filter" and see if it has the same problem. My guess is the problem won't show up.

If it is a chemistry problem in developing try using more developer and see if things change.

Try only one change at a time so you can see when this disappears. If you try more than one change you won't know what the reason was.

[alps-art.ch]

Have you tried a different Neutral Density or other 'dense filter'?


yes, I have four of them - different density in 77 and 95 mm, so I use one or another, depending on the lens - the pattern show up with all filters. Needless to say, any screw-in filter ends up at a random orientation relative to lens/film. So I guess it is rather overexposure.



Try only one change at a time so you can see when this disappears. If you try more than one change you won't know what the reason was.

You are absolutely right here.

[alps-art.ch]

Looking other threads and forums, I noticed people recommend Edwal NFL as a good anti-foaming agent. I cannot find it in Europe. Could someone point out an equivalent out of e.g. these:

https://www.macodirect.de/en/chemistry/black-und-white-chemistry/film-developing/wetting-agent/
https://www.fotoimpex.de/shopen/chemistry/others/

Thanks!
Dimitri.

[Jerry Bodine]

http://www.ebay.de/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xedwal+lfn.TRS0&_nkw=edwal+lfn&_sacat=0

[Drew Wiley]

Some water supplies have quite a bit of natural alkali or carbonate in them. Mixing developer in distilled water cures that. Or it could be severe condensation from
either improper film storage or camera use on a cold day without conditioning the gear to ambient temperature before use. I dunno. Air bells during tray development look different. I've never had a mottling problem like this, with any film.

[Grumium]

Is LFN only referring to EDWAL LFN or is it a general term? What is LFN chemically?

Dimitri, I have/had a similar problems using XTOL that ruined a whole batch of negatives:
http://www.largeformatphotography.info/forum/showthread.php?125997-Uneven-development-of-FP4-in-XTOL-in-JOBO-3010

[Leigh]

The most common reason I have seen for this foam buildup is from using a Yankee style tank to develop 4x5.
Worst experience ever.
This is interesting.

My Yankee tank is my first choice for 4x5 from a selection of several different tanks and systems.

It just shows how different folks have different experiences and outcomes.

- Leigh