Strange Dark line in Negative

[Bruce Watson]

I have got this B/W negative developed in local trusted lab and it has got this strange black line in the negative that is baffling everyone.
This has happened in many negatives I got processed recently. Earlier everything was OK with same lab.

Are the artifacts (the black lines) the same on various negatives, or just similar?

It's unlikely this was caused by something between the scene and the film at exposure time. That is, it's not dust on the unexposed film blocking exposure. It is in fact just the opposite.

It's unlikely to be from a light leak -- the artifact is too well defined.

It's unlikely to be a scratch on the emulsion because that usually leaves clear areas. At least it did when I was tray processing and scratching one sheet with the sharp corners of the sheet on top.

If it were from bending or creasing the film (which can cause density) it wouldn't likely be so well defined, especially on the ends.

This leaves... dirt on the film. Or more likely, some kind of hair or lint. Probably after development. I'd guess from the final rinse, or film drying. And if that's the case, you should be able to see it. Or with lint that size, you should be able to remove it with a good film cleaner (something like PEC-12 that does not contain any water at all so it doesn't soften / swell the emulsion) no matter which side it's on.

Dirt / lint would be much more likely if you are getting similar artifacts from sheet to sheet. If you are getting exactly the same artifact, I'm thinking it's more likely to be a scratch in your light table (or whatever your film is on when you made the picture of the negative for us). If you move your film and the scratch does not move, it implicates the surface under the film.

Or it could be something else entirely. It'll be interesting to see what you determine the cause to be.

[koraks]

> It's unlikely to be a scratch on the emulsion because that usually leaves clear areas.
Not if the scratches occurred when the film was dry, ie before development.

[Deepak Kumar]

All scratches are at different places and of different length & style. There are no visible scratches on the negatives on both side. I have seen negative closely through good loupe. I think pre development scratches could be the reason but I as well as lab technicians have handled the negatives hundreds of time but never faced the problem like this before. I am scanning them now and would post the large file soon.

I have to load all my folders for next project, no being able to identify the cause of such lines, I am just keeping my finger crossed. I am still waiting for definitive answer because scratches usually show up as clear line on negatives.

[Paul Ron]

quick guess... scratched in the holders either loading or unloading.

[G Benaim]

My guess would be scuffs in the pre soak before developer. Do you know how they process the sheet film? If you look at the emulsion side can you see the offending line as a somewhat raised area?

[Deepak Kumar]

I am attaching one more neg image for more info on this issue. As patterns of lines are baffling and not consistent.


Above is one corner of the Negative.

[koraks]

Lots of scratches.

[lassethomas]

To me that that looks like some kind of handling problem. Since there is no mechanical damage they could be the result of light in some way. The long streaks gradually coming in and out of "focus" could suggest some source pin light coming more or less in contact to the film.
How do you load/inload your film? Light leaks in changing bag? Any phosphorescent watches?

Well, at least some suggestions

[Deepak Kumar]

Sorry for late reply, I have concluded that it was film handling issue as with the same set up next batch of dozens of negative have
come relatively very clean with only few negative having one or two small scratches.

[scheinfluger_77]

When I first bought my Mamiya RB67 medium format camera that shoots 120 roll film, all 10 shots on my first roll had a very thin red line showing. I was befuddled? So I took apart the camera. The film back comes off separately. There on the back opening that exposes the film, stuck perfectly straight across at an angle between the top and the bottom was one of my wife's hairs.

Yes, she's a natural redhead.
https://www.flickr.com/photos/alankl...7625602231872/

That look says to me: “Don’t give me none of your yankee, hippie sass”. I like it.