Agfa APX 400 development problem

[Rolly]

Lately I have been noticing a lot of tiny white "dust" on my prints-- when I check the negatives I see matching tiny black motes on the film. It does not clean off with Edwal cleaner, so I know it is embedded in the film.

I have experimented in a fairly controlled way with all the variables in my development process-- I use Kdak HC110 at 70 degreesF for 8 minutes and 10 seconds; one minute flush with filtered water; 5-6 Kodafix; 5 min flush with running filtered water; 1 min Permawash; 2 mins distilled water with Edwal FPN, then hang in a humidified, dust free shower stall.
I tried this method with completely distilled water, using the Ilford method for rinsing-- it does not seem to matter if I use city, filtered water or straight distilled. I don't have any water marks, or airborn dust, so I am leaning towards suspecting my film itself, which is frozen and as yet unexpired though nearing the end of its normal, unforzen shelf life.

The negs are all coming out of the HC110 looking good with plenty of balance and they print out very nice prints-- except for the damn white specks.

Anyone have any ideas or suggestions?

 

[Anon Ymous]

Precipitate in fixer?

 

[rwboyer]

EDIT = ooops I got the white/black reversed when I read your post - so I take all this back. I have no idea?


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Are you sure they are some sort of particle and not just really really small air bubbles? Sometimes it is hard to tell depending on the magnification you are using to look at them. If possible 20x + would probably allow you to be sure.

RB

Ps. most of my black spots on prints throughout the last 30 years were due to something causing some air bubbles early in the development process - It was rare but did happen here and there and I never really could nail down the root cause because it was so infrequent.

 

[Rolly]

RB-- Maybe. I have been assuming, based on 8x loupe, what I was seeing was a tiny particle, but now that I look at the "dust" on the prints, these are often perfectly round and seldom random shapes. I'll try to find a higher magnifyer-- it makes sense that the black specks could also be undeveloped film.

If it were a failure of the emulsion, what kind of symptoms would I be seeing?

 

[rwboyer]

RB-- Maybe. I have been assuming, based on 8x loupe, what I was seeing was a tiny particle, but now that I look at the "dust" on the prints, these are often perfectly round and seldom random shapes. I'll try to find a higher magnifyer-- it makes sense that the black specks could also be undeveloped film.

If it were a failure of the emulsion, what kind of symptoms would I be seeing?

I read your fist post wrong - you have white dots on your prints right? Dark dots could be air bubbles - but you have white dots on the prints - this screams of actually particles (like dust) on/in your negatives. I would have to see the film to even begin to guess. I could be something in the emulsion but that would be highly unusual for a company like Agfa.

RB

 

[ozphoto]

Is it possible dust is landing on the negs during the drying period? I use APX400 all the time, and have never had this experience.
I do remember a friend using a drying cabinet that had not changed the filter for a while - dried their negs but it embedded dust into the emulsion and I guess it kind of "baked" it into the film.

Like the other posters, the only other thing I can think of is tiny air bubbles - but that tiny seems very strange.....

 

[pentaxuser]

I favour something being different in the dust-free shower stall on this or these occasions where the problem arose. For instance have you had any work carried out in or around your shower. I did some drilling in my bathroom recently and while I thought I had wiped all surfaces clean I am still discovering fine dust in all sorts of places.

Another cause, believe it or not, if your shower stall is in the same room as your toilet, is that manufacturers of toilet rolls are making the paper softer to give them a competitive edge. A side effect of this is that when used the paper giives off a cloud of small particles of shreads of paper which settle anywhere. Not an issue for most users but can be a problem if you use the bathroom and shower stall for drying film.

pentaxuser

 

[Rolly]

Thanks everyone. After RB's reply suggesting my problem may not really be air bubbles I rethought the likelihood I have dust. I looked over recent negatives and noticed what could be a water course down the same latitude on all the frames, and wondered then if dust embedded over that trickle of water dripping down the weighted-down negs. I have seen a similar phenomenon lately-- a bunch of frames with dust in a similar pattern running from side to side of the frame, which would be hanging vertically when the negs were drying of course. So I will try an experiment to cover the shower stall with plastic (dust free!) after I humidify the stall. If this fails, I will move on to do a test with another brand of BW film versus APX. Other than particles in the developer/fixer, it is either dust or bad film.

I have noticed on occassion some of my APX develops with smeared areas, as if either the emulsion has gone haywire or perhaps the developer was weak and did not fully develop little areas of the film. I have seen this effect on maybe 5 of the past 30 rolls, and in one case identified spent developer as the problem. But in this present case, the HC110 was fresh mixed, and as I say, gave me really nice looking frames, other than these white dusty-looking thingamabobbies.

Appreciate the help. Thanks. rolly

 

[Rolly]

FOLLOW UP: My experiment did confirm what the dust-sayers suspected. Although my shower stall goes almost to the ceiling, dust must have been entering over the stall, despite humidification of the entire bathroom. I simply sealed the airspace around the stall up to the ceiling. Lesson learned.Thank you to all who offered their insights.