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lenser
6-Mar-2012, 16:47
I've been processing film since about 1965 and this is by far the strangest thing I've ever had happen.

Here are the parameters:

Two rolls 120 processed at the same time, in the same tank using HC110 at 68-70 degrees.

Temps of all chemistry and wash water were within 5 degrees of one another.

Used a Kindermann rotational processor.

Used the appropriate time on the development chart less 20% to allow for constant agitation.

One roll was Tmax 100, the other was Ilford Pan F Plus (long outdated)....both exposed at normal film speed.

In the images below, the church doors are from the roll of Tmax which all came out perfectly.

The two frames that include the cars are from the roll of Ilford and show the strangest pattern I have ever seen on any film. It is almost like a texture screen has been applied and it matches on each and every frame throughout the roll but does not appear on any of the blank areas of the margins or between frames as you can see. No, I did not shoot through anything except clear air.

Since both rolls were processed together and under normal processing parameters, I can't imagine that this is in any way a processing artifact.

Unfortunately, I can't remember which of my three medium format cameras was used on the weird roll, but my diciest one, (an ancient Kalimar 660 which I was testing) was used on the church image and of course the rest of that perfect roll. The other choices would have been Hasselblad or Yashica Matt 124G, but this looks like no camera or lens artifact that I've ever seen. Nor does it resemble any light leak I've ever encountered.

Best guess so far came from a friend who opted for a bad roll from the manufacturer which only activated when exposed to light through the lens, but showed nothing on the cleared film areas post fixing and washing. I have my doubts, but I have no other opinions.

I am completely at a loss on what could cause anything remotely like this, so everyone, please chime in with your best guesses.

Thanks in advance.

Tim

Brian C. Miller
6-Mar-2012, 17:05
For the Ilford Pan-F, what was the time between when the roll was exposed and when it was developed?
Also, what does the unexposed film look like? Is there anything funky there?

lenser
6-Mar-2012, 17:18
Both rolls were exposed over a year ago and recently found in a desk drawer. As stated, there is no pattern anywhere on the film other than within the frames of each exposed image. The rest is absolutely clear.

Jay DeFehr
6-Mar-2012, 18:35
I've seen this before with some very old Russian film. I think it's from the backing paper.

Nathan Potter
6-Mar-2012, 19:35
I might guess condensation on the undeveloped film at some point; although the degree of uniformity is surprising.

Nate Potter, Austin TX.

Jay DeFehr
6-Mar-2012, 19:58
If you still have the backing paper, look for the pattern on it.

lenser
6-Mar-2012, 20:25
Jay, I've done that and I honestly can't see one, plus that pattern would have to be on the film back and I see nothing there. It seems to actually be within the processed emulsion. The mystery continues.

Nathan, I had not thought of condensation, but I am lead away from that thought because there is absolutely clear film between the frames and along the edges and at the ends. Every idea I have just seems to self destruct in the face of the fact of clear base film surrounding each frame. You are correct about the uniformity. It exists on all twelve frames with remarkable repetition of the pattern.

polyglot
6-Mar-2012, 20:59
The film emulsion touches the back of the paper when it's rolled on the spool, which is how you can get paper patterns in it.

You're lucky there's an image at all; Pan-F fades rapidly if left undeveloped.

Winger
6-Mar-2012, 21:04
No clue what it's from, but I'd guess that the artefacts not showing between the frames doesn't matter. The dark areas of the photos don't seem to show anything as obvious as what's in the sky. That says to me that it shows more in areas with more exposure to light - which means it may not be just within the frames, but also between, just not noticeable because those areas weren't exposed.

Jay DeFehr
6-Mar-2012, 21:21
Here's one from my old roll of Russian film:

69703

Looks similar, to me.

lenser
6-Mar-2012, 22:01
Polyglot. All I can say is DUH!. That's what I get for answering when I need a nap. I just pulled the roll of backing out of the trash and there is indeed a pattern that faintly shows over the entire white outer surface. So now the questions is, what creates this pattern? Could it be some sort of out-gassing from the paper, or a raised printing artifact from the paper manufacturing process that literally embosses on the film? A chemical reaction between the inks in the white outer coating? Any ideas?

lenser
6-Mar-2012, 22:03
Jay, I agree. It is very similar. Could this be a problem with the paper manufacturing process in European papers as compared to other manufacturers? If so, I would think it would appear more often, but I'm open to suggestions. Maybe an aging issue that causes a breakdown of the coating components in the paper?

Leszek Vogt
6-Mar-2012, 23:53
My first thought was "reticulation"....but that would mean that you'd use higher temp in your chemicals....it does have somewhat similar look. Is it possible that the film was cooked....I mean it sat in warmer places than it should have ? Not sure....though I don't take chances and refrigerate the film. Another anomaly is moisture getting into the film and then being processed. I had mot. pict film processed after the 35mm cartridge swam in the cooler....I just want to say, forgetaboutit! Need an emicon with rolling eyes.

Les