Neopan 400 white dots - what's going on here?

jonmanjiro

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I recently developed 18 x Neopan 400-135 rolls, all using the same developer and same fixer. I developed 6 rolls at a time using 3 tanks, so 2 rolls in each tank. All the rolls came out fine except for 2 rolls developed in the same tank. As per the sample shot below (click to see a larger image) there's white dots everywhere on the scans of these 2 rolls only. Beats me why only these two rolls are like this... what the heck happened here folks? :confused::confused::confused:

 
The weird thing is I used the same developer for four other rolls at the same time in two other separate tanks, and they were fine.
 
You will have to check the negatives. There doubtlessly is something black and opaque in or on the film at each dot. But only inspection of the negatives will tell what - it might be dust that embedded in the drying process, particles in the washing water, a precipitate in developer or fixer, a reaction between the developer and some other agent (fixer carry-over, or water pollution) that chemically exposed some grains in the film, or (if the drying was very prolonged or you left the film in water over night) even microbial growth.
 
Jon I did a quick Google search, which supports sevo's suggestions - another possibility is a reaction with the stop bath, but others have not been able to confirm that. Do you have a low power microscope to examine the neg?
Edit: it looks like PhotoFlo may be another contender, see here.
 
You will have to check the negatives. There doubtlessly is something black and opaque in or on the film at each dot. But only inspection of the negatives will tell what - it might be dust that embedded in the drying process, particles in the washing water, a precipitate in developer or fixer, a reaction between the developer and some other agent (fixer carry-over, or water pollution) that chemically exposed some grains in the film, or (if the drying was very prolonged or you left the film in water over night) even microbial growth.

I can see the black dots on the negative with a 40x loupe but have no idea what they are.

I used the same developer, fixer, and washing water for all three tanks (2 rolls in each tank) that I processed at the same time. I developed the film immediately after preparing the chemicals, then hung the film to dry for four to five hours, and then scanned all six rolls. Two rolls from the same tank were affected, but the other four rolls from the remaining two tanks were fine.

I guess its possible that one of the three tanks had some kind of contaminant in it, though I don't really see how that could have happened as I always develop six rolls at a time using three tanks and handle each tank identically.
 
Jon I did a quick Google search, which supports sevo's suggestions - another possibility is a reaction with the stop bath, but others have not been able to confirm that. Do you have a low power microscope to examine the neg?
Edit: it looks like PhotoFlo may be another contender, see here.

Thanks Lynn. I use DryWell, which is Fujifilm's equivalent of PhotoFlo, but as with the developer and fixer, the exact same DryWell went into all three tanks but only the films in one tank got the dot disease. Very weird.
 
Jon, looks like you are experiencing the same "white spots" infamous problem as many of us had with Acros and, sometimes, Neopan 400. This looks like some crystals of a chemical of some sort trapped into the negative telling a mismatch between a component of the developer (probably genol) and the film base.

When looked at with a lupe, the negative displays many black crystals trapped into the emulsion and this is definitely not dust particles coming while the film was hung for drying.

IIRC you had opened a thread about this some years ago and some people had written that I was totally wrong by thinking that this was a specific problem with Fuji B&W films.

You have a very good memory, Nicolas! That previous time I had developing problems with Neopan 400, I traced the cause to gunk buildup on the Patterson rolls which got dislodged when banging the tanks to remove air bubbles during developing. IIRC at the time, Gabor suggested that gunk buildup may be the problem. After thoroughly cleaning the rolls, I haven't had the problem again.

As for this new problem, you may well be right about it being the white spots. I'll have another look at the negs, this time much more closely!
 
Do you remember in which order of the 3-tank batch and the overall 18 rolls the affected film was processed? Was any of the chemistry powder based?

The link above is interesting and points to silver particles suspended in reused fixer as a possible problem.

If it was in the developing stage the only thing I can think of is super-fresh not fully mixed developer where some powder crystals adhered to the film and caused over development. Seems kind of a long shot.

I assume the black spots on the film are also visible in the film rebate area?
 
As for this new problem, you may well be right about it being the white spots. I'll have another look at the negs, this time much more closely!
I still have my affected Acros negatives (shot in 2009) in my folder. I'll scan some tonight with my film scanner and will post 100% crops so we can compare how the spots look like... ;)
 
Here we go.

First, one of the rare pictures from those Acros rolls shot in 2009 for which I took some time to remove the spots with PhotoShop (what a bitch of a job).

Then, a 100% crop of the center of the image (negative then inverted) scanned a few minutes ago at 2820 dpi with a film scanner.

The spots looks like randomly located opaque crystals trapped into the emulsion. The whole frames of the whole Acros rolls shot back then were like this.

The negative is immaculate when looked at with the naked eye and even with an office lupe from an oblique angle. This had never happened to me with any other film and this never happened to me again. Only with all the Acros rolls developed in the same D76 1+1 I have been using for decades and which I am still using now with no problems with many other films.

1/
carnon.jpg


2/
spots.jpg


3/
spots2.jpg
 
It's crap in the water......

I used to get that a lot, went away when I started to filter the water i use for development, fixer and wash.
 
Jon, I had the same thing happen to my last batch of 35mm Neopan 400, about 15 rolls did this.
My Tmax and TriX did not do this, but the Neopan did.
I will post a sample later to show, as what happened with mine looks different then what Highway 61 posted.
 
You're right, it's some intelligent crap which had decided to get stuck on Fuji Acros negatives and not on all the other films I was (and still am) developing with the same (pure) water. :cool:

It can happen. That is, not in terms of things in water selectively sticking to some particular film, but heavy metal ions (usually copper and lead, thanks to the installation tubing) may interfere with some films and developers while they do not matter in other combinations.
 
It can happen. That is, not in terms of things in water selectively sticking to some particular film, but heavy metal ions (usually copper and lead, thanks to the installation tubing) may interfere with some films and developers while they do not matter in other combinations.
Not too sure. I don't use tap water to prepare my D76 stock solution, nor any to prepare the 1+1 work solution. Nor to prepare the stop bath solution. Nor to prepare the fixer solution. And I always use the same chemicals to develop the films I'm myself stuck to.
 
Not too sure. I don't use tap water

Well, you must have used SOME water, probably not fresh out of your own double distillation. Bottled de-ionized water is fine for household use, but it might not be photochemistry safe - something might leach out from the container, and microbes might grow in it. And reverse osmosis water can be subject to partial filter failures, too.
 
I do use some Volvic or anything equivalent, not bottled de-ionized water. And this has NEVER happened with ANY film other than several rolls of Fuji Acros developed from time to time during several months with renewed solutions. As soon as I have given up with that film, it NEVER happened again. I have developed THOUSANDS of films since the early 1980s and this has NEVER happened to me BUT for almost ALL the Fuji Acros which I developed.

I will add that the SAME problem happened to MANY FRIENDS of mine with the SAME FILM and, like me, they had NEVER got this with any other film.
 
I will add that the SAME problem happened to MANY FRIENDS of mine with the SAME FILM and, like me, they had NEVER got this with any other film.

Fuji is known to have used some rather odd additives in their black and white films, so it may well be that they have very specific pollution vulnerabilities not shared with any other film.
 
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