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Leonard Evens
26-Apr-2006, 07:36
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Can anyone explain what the curved lines below are?&nbsp;&nbsp; They
definitely appear to be in the image and not a surface imperfection on
the negative.&nbsp;&nbsp; What you see is a small section taken from a
4 x5 negative which was shot with a 90 mm lens at f/16,
1/60.&nbsp;&nbsp; Note the blurring of parts of the curves.&nbsp;&nbsp;
My first thought was that perhaps there were cables attached to the
structure blowing in the wind,&nbsp; but there wasn't that much wind
that day, and in any case I took another picture of the same scene
several minutes later which doesn't show even a hint of these
curves.&nbsp;&nbsp; Another possibility is fuzz of some sort in the
film holder.&nbsp;&nbsp; The section is close to the edge of the frame
on the far side of the slide away from the slide handle.


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Walt Calahan
26-Apr-2006, 08:13
The little white spots are from dust when you scanned.

The big black line is a hair or other stringy bit to stuff on your film when you made the image. The object on your film blocked the light thus creating a shadow on your film which appears as a black irregular shape going in and out of focus. The further the object was from your film the more out of foucs it is.

Clean clean clean, but it still happens to almost everyone from time to time.

Hey that's why the invented the cloning tool and healing brush in PhotoShop. Grin.
Al Seyle
26-Apr-2006, 08:30
I agree with Walter. But why does the sky change color around the subject(s)? Is this something in the scanning process?
Leonard Evens
26-Apr-2006, 09:16
Thanks for the comments.

I know what the white spots are. I am very careful about dust, and my b/w negatives require very little or no spotting. But I have my color negatives done at a commercial photo lab, and while they are pretty good, they don't do as well as I do. Still, if you magnify enough, which was the case here, you are bound to see some spots. It is just not worth the effort to remove them all if they won't show up in any plausible print.

I know all about cloning, and I've already removed the offending material from the full image.

One of my first thoughts was that the extraneous lines were from hairs in the film holder, and I suppose that must be the explanation. But I always follow the same procedure, checking my holders caerfully before loading, and I've never seen anything like this before. Although extraneous hairs is the most plausible explanation. I wondered if anyone could think of another possibility.

The halo that Al noticed results from sharpening. It is not in the original scan which was done with an Epson 3200 scanner. The section shown is about 10 x 20 mm from a 96 x 120 mm full frame. I applied an unsharp mask without too much care to empahsize the extraneous curves. Usually I don't bother to apply any sharpening or I do so very carefully. It is also possible to remove the halos, if absolutely necessary, by careful cloning. I have sometimes done that in cases where you couldn't see it at any reasonable magnification for a final print but where it still seemed to have a subtle effect on the image.
Walt Calahan
26-Apr-2006, 09:26
We all try to clean clean clean, but some times the simple act of removing the dark slide can dislodge a loose hair into the air and have it settle on the film.

Also the film can get a charge, so when the dark slide is removed, the film attracts dust and hairs floating into the camera. Good to vacuum out the inside of one's bellows from time to time.

Then there is simply bad luck. The story of my life. HA!
steve simmons
26-Apr-2006, 09:37
I would agree that the black is casued by that area of the film not being exposed. Something was in front of the film but close to it - otherwise the lines would be more diffuse.

On another note, Leonard, I sent you a private e-mail. Did you get it?

thanks

steve simmons
GPS
26-Apr-2006, 09:44
It's definitely not hair in the image. It's some kind of a cotton or textile fibre. It could have come from where you place the film holders or just been blown into it.
Patrik Roseen
26-Apr-2006, 09:50
If it is like you say that you had this developed in a lab ...the 'hair' could have come from the developer tank. If it sticks to the film during development the negative will not get developed in this area which means it will look as if the underlying film did not receive any light during exposure. It could have come off later in the process (in the rinse). The fuzziness in the top of the picture could be the 'item' moving, i.e. not attaching as firmly as the other parts. Is this 'hair' close to the markings where the film was held during development.

I myself give my development tank some extra shake now and then to make sure that any particles attaching to the film, from the time I take the undeveloped film out of the holder until it get's into the developer, don't stay there during the full development cycle.

I also carefully vacuum my camera bellows and try to make sure that 'things' do not enter the front of the bellows while changing lensboards.
Wilbur Wong
26-Apr-2006, 11:05
I agree with hair or some kind of fiber. Where it is fuzzy is probably the fiber being further away from the film surface thereby being out of focus.

I have to admit that the particular location of these "lines" look very suspiciously emanating from the top of this building. (I am guessing that I am seeing glass cleaner platforms etc. and that this isn't really a dedicated transmission tower with ufo type transmissions)

In a side note, I once had a series of jagged light streaks across color slides from a 35 mm and motor drive. I finally figured they were static electricity discharges during low temperature low humidity conditions with a rapid film movement.
Leonard Evens
26-Apr-2006, 12:43
After reading all your answers, I've decided it must have been a fine "net" of fibers or hairs which somehow got between the flap of the film holder and the film. But it is surprising how thin it must have been. At 3200 ppi, which is about 125 pixels per mm, it is about 5 pixels wide. That means the debris, whatever it was, was about 0.04 mm or 40 microns wide. That seems more consistent with very thin human hair than with thread.

Another interesting note. The tower from which the threads seem to emanate is part of new construction in our downtown, and it seems to produce some quite high winds. At various times, they do have cables flying about in the wind, so at first glance, it was not inconceivable that what I saw was actually in the scene. Given that the wind was not specially high that day and it was missing from another exposure taken minutes later, that possibility was excluded. But it does emphasize that sometimes it may be difficult to distinguish something in the scene from an artifact produce in this or another way.
GPS
26-Apr-2006, 13:36
A nice try, Leonard. I can just tell you that it took me a fraction of a second to identify the thing. Once I was blackening the inside of a camera. As the paint was drying it caught a fiber that stayed there. It took several rolls of film to shoot only to see on all of them this fiber - in several positions, sharp, less sharp etc. etc. It was exactly as you have it on the picture. There is ana infinity of fibers that can have all the thickness you think only a human hair can have...
Frank Petronio
26-Apr-2006, 14:00
RIT offers courses in photo analysis. It much in demand by the CIA and military. Perhaps you could send there as an example?
paulr
26-Apr-2006, 14:44
Isn't it possible that there were just a lot of huge, gyrating tentacles sprouting from the antenna?

"When you hear hoofbeats in Texas, think horses, not zebras."
David A. Goldfarb
26-Apr-2006, 17:33
It could be some frayed fibers from the light trap (had this once with a 35mm camera and reloaded film cartridges). On some holders it is possible to inspect and replace the light trap, so you might check this if possible. If you load film in a changing bag or tent that could be another source. Of course, if you load in the darkroom, it could have also come off of whatever you were wearing, and you wouldn't have noticed in the dark. And if it's really hair, it could have come from your head. I wear a hat when loading, mainly to prevent dandruff from falling on the film.
Jonathan_6488
27-Apr-2006, 01:35
Well, much as I hate to say it - my best guess is pubic or other body hair from a caucasian person. It's definitely hair. You can tell from the structure of it - it's grown - not manufactured. Especially from the varying (decreasing thickness). And you can tell it's not hair from the head because the structure, again, would result in a highly matted grouping - as though designed for trapping air and keeping the area warm. The slight curl and the kink to it also tells you that it's got a flattish cross-section (not round - as you'd find in an asian sample - that's why asian hair tends to be straight). There is a slight chance it's from a sweater - if it's pure wool. But I haven't seen any wool kink QUITE that way.

Check the film holder dark slide (it WAS large format, right?). My best guess as to source (if this isn't a troll - which I'm not sure of) would be there's NICK in the edge of that slide - and perhaps some of the offending matter might have been on your clothing (or else it's your arm hair - which would be of a more regular structure - and you PROBABLY would have noticed it).

I LOVE a good mystery.
Jonathan_6488
27-Apr-2006, 01:56
on second thought... it COULD be cat hair. I was just inspecting my cat's hair. That would account for the small diameter...
Frank Petronio
27-Apr-2006, 06:11
Another reason why i keep my pants on when loading film.
tim atherton
27-Apr-2006, 09:14
"on second thought... it COULD be cat hair. I was just inspecting my cat's hair."

pubic cat hair...?
Jonathan_6488
27-Apr-2006, 10:23
Now that's just nasty.
GPS
27-Apr-2006, 13:29
I've seen many cats shows. I still have to see a cat covered with "pubic hair from a caucasian person". What a guess!