Strange dimples on Negatives

RoboRepublic

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Hi folks,
On Tmax 400, I am seeing these dimples form on the negative. They are difficult to photograph on the negative, but I can provide samples if thats necessary.

The work flow is like so: 7 minutes in XTOL, 30s ilfostop stop, 5 minute flix. 3x illford wash from the tap (water is mineral heavy) followed by a 15 minute soak in distilled water with 20x inversions every 5 mintues. The water runs slightly pinkish. After this I hang to dry with out any other intervention.
This has successfully removed most deposits from other film stocks (FP4, Delta 100, Kodak 5222), but its leaving my Tmax 400 looking like so. Is the final distilled soak too long? Could that be causing this?



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Xylo

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Looks like a bunch of pinholes in the emulsion. But the edges look like water droplets.
What bugs me is that both these things usually don't go hand in hand.
I know that too strong an acid stop can sometimes cause pinholes, but I've never experienced this myself.
 

MattKing

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What format is this?
 

albada

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I have hard water like you, and I do the same final step as you -- wash with distilled water with no photoflo. The results are always perfect.

As @Xylo said, those look like water spots. I'll guess the dark center spots are where the minerals concentrated during drying.
Here's my guess: Your distilled water is contaminated. You might have had much carry-over of hard water in the tank, or possibly your jug of distilled water was contaminated when you poured leftover water back into it sometime ago. Here's an idea: Before filling with distilled water, remove the top of the tank, and separately shake-out all the water you can in both tank and reel. You can test your distilled water by putting a few drops on glass and letting it dry.

Mark
 

FotoD

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I don't know what this is. But the shape makes me think of solid particles on or in the emulsion. Maybe a manufacturing defect?
 

mshchem

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Are these an artifact of "scanning"? Some form of Newton rings???
 

MattKing

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mshchem said:
If the dots are black in the print would means these are lighter, less density in the negative.
Click to expand...

Either that, or they are areas on the negative that have less residue on them than the rest of the negatives.
 

ic-racer

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There has been some damage to the film. How old is it, where did it come from?
 

koraks

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RoboRepublic said:
They are difficult to photograph on the negative, but I can provide samples if thats necessary.
Click to expand...

I understand the difficulty, but an attempt would be appreciated.

The problem is puzzling for the reasons already outlined above: the white crescents are reminiscent of water spots, but the dark dimples are apparently minus density and that's the opposite of what water spots would do/be. Given their spatial relationship, they do seem to be part of the same effect, although I have a small amount of doubt about this.

In any case, the best photos you can manage of the actual effect as visible on the surface of the film would be very helpful indeed.
 

Sirius Glass

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Possibly from the film getting kinked while loading on the reel.
 

Sharktooth

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When you mix up your X-Tol, are you also using distilled water? I'd use distilled water to mix your fixer and stop as well.

With your final soak, it's probably not doing much to leave it in for a long time. It would be better to do a few short soaks and dumps, to get rid of any remaining minerals. A long single soak just leaves the remaining minerals still hanging around.
 

Xylo

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This is really puzzling as if it was undiluted developer crystals sticking to the film, the spots would be bright white when enlarged.
Somehow, I'm not really thinking this has much to do with the hard water. We have pretty hard water near Montreal (you should see my humidifier after a week), and I've never had anything like that.

Do you pre-wash the film before development?
Did you let the film sit idle for any period of time in an empty tank before moving on to the next bath?

It looks like there was something stuck on the emulsion that acted as a nucleation site for droplets of water to stick to and then dry a bit. Then that particle somehow got mechanically removed taking with it a bit of emulsion.

That's the best I can come up with so far.
 

john_s

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The marks look somewhat like faint airbells I got when I started using a new film (120 Neopan400). They were faint darker little disks visible only in clear sky part of the pic. Despite not having had airbells for at least 45 years. I think that the airbells dissipated after a minute or two of developing and left a disk of less than normal density. Mine did not have the "halo" that the OP's example has.
I found that a vigorous 3 minute pre-soak in plain water prevented it in subsequent films, and I now do it always.

edit: thinking about the OP's "halos" and me not getting them, maybe our agitation styles are different. Just a guess.
 
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