black stains on negative

[odewaele]

Hi, community members,
I have 4 or 5 pictures per film (36 frames Ilford FP4+) that show black stains on the negative : they show randomly on the negative and can have different sizes.
I post 2 shots that were taken in similar conditions (part of the scenery is identical) at an interval of seconds.
They were shot with Nikon F6 50mm 1.8.
I developed the film with Ilfotec DDX / Ilfostop / Ilford Rapid Fixer.
Has anybody got a clue to explain where the problem could come from?
Thanks in advance!

 

[pentaxuser]

So these are black marks on the negatives but only on 4 or 5 frames. Are these black marks visible on the negatives and if so are they part of the emulsion such that you cannot rub them off with a cotton bud and wetting agent? . That is they are or appear to be part of the emulsion?

Thanks

pentaxuser

 

[odewaele]

Thank you Pentaxuser for your advice.
I've rubbed the black "stains" on the negative with a cotton bud and wetting agent. No change is to be noticed : it seems to be part of the emulsion.
Could it be a problem with the camera itself (F6 bought brand new in Feb 2020)?
I also devep 120 films and have not noticed such stains on those negatives.
Thanks.

 

[pentaxuser]

Wait until others respond to hear what ideas they have but I don't know what might cause black areas in the negative that appear to be part of the emulsion. Unless others can suggest a cause that is not an emulsion problem then you may have to contact IlfordPhoto and explain the problem in as much detail as you.

If you have kept the canister then let Ilford know the batch number on the cassette and where you purchased the film. Do you know the expiry date of the film?

pentaxuser

 

[YoIaMoNwater]

Could be something to do with the developer or the water you used for dilution? I've only noticed black spots on my color negative from a depleted/contaminated developer, though I haven't encountered anything like this on bnw negatives.

 

[foc]

Black on the negative would suggest something has blocked light from reaching the negative.
From looking at the first image, the two marks (showing white in the positive image) look like something stuck to the negative.

Do you use the DDX developer as one shot?
If you examine the affected negative on the emulsion side (matt side) does the black mark appear embedded in the emulsion or part of it?
It might help if you could upload a shot of the neg strip, full-on and sideways view.

 

[Andrew O'Neill]

If the blacks spots are in the emulsion, there is nothing you can do about them. Could have occurred at Ilford.

 

[odewaele]

Hi, YolaMoNwater,
I think I can exclude the developer dilution as a source of the problem : I have experienced developing other negatives (Kodak 120 Tri-X 6x6) before and after the Ilford FP4 and had not such problems.
Thanks for asking.

 

[MattKing]

Black on the negative would suggest something has blocked light from reaching the negative.

I think this should say "Black on the negative would suggest extra light has reached the negative."
But I agree - it look like some sort of debris on the negative.

 

[odewaele]

Black on the negative would suggest something has blocked light from reaching the negative.
From looking at the first image, the two marks (showing white in the positive image) look like something stuck to the negative.

Do you use the DDX developer as one shot?
If you examine the affected negative on the emulsion side (matt side) does the black mark appear embedded in the emulsion or part of it?
It might help if you could upload a shot of the neg strip, full-on and sideways view.

Hi, Foc,
Yes, DDX developer is used as one shot : I've developed other films (Kodak 120) with not problem at all.
I have difficulties answering your question about the mark being embedded in or part of the negative. I've followed the instructions of a previous post to rub the surface of the mat side smoothly with a cotton bud with no result, expectedly.
I have tried to take a shot of the emulsion side (not easy without a macro lens).
I post the result below.
Thanks for viewing and answering.

 

[MattKing]

Check the shiny side too.

 

[Andrew O'Neill]

I see white spec on the film, as well as what appears to be a light leak.

 

[pentaxuser]

I see white spec on the film, as well as what appears to be a light leak.

Yes, I agree. On the frame on the right there is clearly a light leak on certainly the edge and then it looks as if there is a black light streak into the frame
OP which frame is this in terms of a number. It may be the angle at which you took the picture of the frame but neither frame looks right. I woud have expected to see what's on the frame much more clearly. They look as if they were taken in a grey fog that has prevented any detail from being easily seen

Do all the frames have this foggy look?

pentaxuser

 

[odewaele]

Yes, I agree. On the frame on the right there is clearly a light leak on certainly the edge and then it looks as if there is a black light streak into the frame
OP which frame is this in terms of a number. It may be the angle at which you took the picture of the frame but neither frame looks right. I woud have expected to see what's on the frame much more clearly. They look as if they were taken in a grey fog that has prevented any detail from being easily seen

Do all the frames have this foggy look?

pentaxuser

Sorry for the poor quality of the neg pictures.
I've put it in my negative carrier which gives it a better look of the shots below
I've made a shot of the base side and 2 shots of the emulsion side. There's no leak to be noticed, except the two dots.
I also upload a scan of the picture with "damaged emuslion" (shot n°35) for further readers to compare as well as picture n°34 on the same roll which shows no sign of "damaged emulsion".
Thanks

 

[pentaxuser]

Thanks for the pictures. Have you contacted Ilford yet? Unless somebody here can come up with an explanation that covers everything you have said and everything you have shown us that rules out a problem with the emulsion on certain frames then the odds would seem to favour the problem lying ( literally in your case) in the emulsion and if so Ilford needs to know about this

pentaxuser

 

[winger]

Could it be dust from the edge of the film canister or inside the camera that got stuck on and then made permanent by the chemicals? The other option besides asking here would be to send Ilford the affected section of film.

 

[odewaele]

Thank you all for your help and legitimate suggestions. It has helped me to rule out certain possible causes.

Here are the next steps I'll try to solve my problem :

• contact Ilford as suggested
• make more tests with another roll of Ilford FP4+ (of the same batch) and have it developed by a professional lab
• make other tests with a Kodak tri X

I'll keep you informed in this thread as soon as possible (being an amateur photographer, this could take some days ).

 

[pentaxuser]

Thank you all for your help and legitimate suggestions. It has helped me to rule out certain possible causes.

Here are the next steps I'll try to solve my problem :

• contact Ilford as suggested
• make more tests with another roll of Ilford FP4+ (of the same batch) and have it developed by a professional lab
• make other tests with a Kodak tri X

I'll keep you informed in this thread as soon as possible (being an amateur photographer, this could take some days ).

Thanks for that. It is always useful to know how a problem is eventually solved. It satisfies our natural curiosity and more importantly it can help us to help someone else who may report a similar problem in the future

pentaxuser

 

[Kino]

What is interesting and confusing is that the "debris" is the wrong polarity for a physical artifact on the emulsion surface during exposure. It should have blocked the light and be the opposite (clear) on the negative if it were dirt or other physical debris.

I would guess that this material somehow found it's way onto your drying negatives and deeply embedded itself in the emulsion. It almost looks crystalline in structure...

 

[MattKing]

Tell us how you wash and dry your negatives, including any surfactant (such as Photoflo) you may use to aid in drying.

 

[odewaele]

Tell us how you wash and dry your negatives, including any surfactant (such as Photoflo) you may use to aid in drying.

Hi, Matt,
Once fixing is complete, I connect my Paterson tank to a running water tap and wash the film for 10 minutes. Running water in my area is famous for being hard water.
Then I empty the tank and wash it for 2 minutes with demineralized water and wetting agent (1+200) with 2 agitations after pouring.
Thanks.

 

[foc]

I think this should say "Black on the negative would suggest extra light has reached the negative."
But I agree - it look like some sort of debris on the negative.

Thank you Matt for the correction, my brain was probably getting tongue-tied. Thankfully you knew what I meant.

I don't know the Nikon F6 well enough, but could there have been a tiny amount of debris (say from light seal, or mirror box "velvet" or just fluff) that stuck to the film frame at the moment of exposure and then dropped off?
A case of the floating debris?

 

[Pieter12]

Thank you Matt for the correction, my brain was probably getting tongue-tied. Thankfully you knew what I meant.

I don't know the Nikon F6 well enough, but could there have been a tiny amount of debris (say from light seal, or mirror box "velvet" or just fluff) that stuck to the film frame at the moment of exposure and then dropped off?
A case of the floating debris?

It wouldn't be a black mark on the neg, it would be white.

 

[pentaxuser]

Thank you Matt for the correction, my brain was probably getting tongue-tied. Thankfully you knew what I meant.

I don't know the Nikon F6 well enough, but could there have been a tiny amount of debris (say from light seal, or mirror box "velvet" or just fluff) that stuck to the film frame at the moment of exposure and then dropped off?
A case of the floating debris?

This makes sense to me. Some movement of action stirred up some debris such as each time the film moved. It landed on the frame then the picture was taken and the subsequent movement of the film dislodged it again after the damage to the frame in terms its effect on the exposure of that part of the film. It certainly explains why there is nothing to be seen in terms of a foreign body stuck to the film

pentaxuser

 

[foc]

It wouldn't be a black mark on the neg, it would be white.

Thank you for the correction, my brain must be addled.

I promise I won't make any more suggestions.