With laminar flow, lids on or off while tapping, etc we're grasping at straws here. But here's another, are the reels exposed to fixer powder when you are mixing it?
With laminar flow, lids on or off while tapping, etc we're grasping at straws here. But here's another, are the reels exposed to fixer powder when you are mixing it?
I use Kodafix liquid fixer concentrate.
I agree it's an exercise in grasping as straws. For what I am doing, it's not been so bad as to ruin a negative, but it would be nice to know what is causing the problem.
Sanders
Grasping at Straws?? Shoot some grey cards, adjust your methods in a controlled way. ... This is a problem that only you can solve with testing. I don't think anyone here *myself included* can answer this one.
Not enough developer/fixer: I fill my tanks to overflowing.
If you're filling to overflow, could it be that therefore there's no room for a layer of air at the top? This would diminish the effect of the agitation "wave" that occurs within the tank during inversions, leading to inadequate mixing.
Mike, I believe (and since I can't see inside the tank, the verb here is "believe") that the agitation comes from the reels sliding up and down inside the tank, through the chemical. I do not believe that "wave action" explains it. But it is only a belief.
Sanders
Here's another thought...
If you have some chemical contamination on your dominant thumb (sometimes a chemical can be well-absorbed into the skin), it would enter into contact with one side of the film as you load....
Blaming the film emulsion is the easiest route to go . If that works for you. I personally would do some of the testing that I and others have suggested. Why did you start this thread anyways if you are not prepared to do the legwork?
Bob, why the confrontational tone? I was only taking your idea a step further, to what I believe was its logical (and necessary) conclusion.
The problem is that I have already done the things the others suggested. Of course I will now go and vary each of the steps of my processing. Each step has been refined through years of processing many many thousands of rolls of film, without ever observing this problem before. But I will now abandon each, one by one, and see what happens. And somewhere in the process the problem will go away, and whatever it was I changed, I will now incorporate into my workflow. Of course I will do all of that.
But will what I change, be the solution to the problem? Or will it (more likely) merely coincide with some other unseen change? Then I will have committed to practice some false solution to a problem that did not exist. Darkroom practice is rife with stuff like this. How many chestnuts about processing film are created in just this way?
You suggest that attributing it to the emulsion is a cop-out. I suspect it is the most plausible explanation. But that is only my suspicion, based on the location of the splotches. It's too bad PE isn't reading this thread. It would be interesting to read his thoughts on the subject.
Why did I start the thread? Because I had hoped that maybe, someone, somewhere, had seen just this artifact, and could attribute it concretely to a specific problem. Alas, only half my hopes were fulfilled.
Sanders
I do believe blaming the manufacturer is a cop out.
I went back and reread Aurelien's earlier thread:
(there was a url link here which no longer exists)
He reports seeing the same effect (a strip of splotches along the right rebate) in all three rolls, processed together -- of different films. Assuming it is the same effect, that suggests several things:
-- It isn't a flaw in the film emulsion.
-- It isn't due to something happening at the top of the tank (foam, too little developer, too much developer).
-- It is odd enough that the effect is seen only on one edge, but odder still that it is seen always at the right rebate. One would expect to see it at the left rebate half the time, if it were a development problem.
I am beginning to wonder if it is an exposure artifact or some sort, rather than a development artifact. I am shooting a Rolleiflex. Aurelien's example comes from a Rolleiflex. There is a toothed wheel on that side of the camera that tracks the film for the frame counter. It bites the film in the rebate, but maybe it sometimes deflects the film enough to affect exposure. Maybe not.
Sanders
Ok now you are getting somewhere. I was hesitant to say the minus density looked like sprocket holes as it was obvious to me that he was using a medium format camera. I did not know that the camera you and he are using produces sprocket holes. ... Adjacent problems close to edges of film and sprocket holes are prevelant in 35mm work.
..this is not a film problem, it is a processing problem.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?