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Sweep
23-Apr-2019, 12:35
Dear all,
I would appreciate some guidance on what you think is causing the black dots on my negatives (white on scanned to positive).
I am developing FP4+ in ID11 for 9minutes 20seconds in my Jobo but I also got the same thing with PanF in ID11 at 7minutes 13 seconds.
It could be something as simple as an exhausted developer but I keep it in a concertina container without air.
What I did find unusual was that it only seems to affect the mid-grey of the sky as the snow is pure white and the hull of the boat is pure black; very odd. I have checked the negative and can confirm it's not a scanner issue as the spots are clearly visible.
Ok, I appreciate that these are only 645 but I dare not run any 10x8s until I am confident of the problem. Jobo's are great but if you do get a problem you only discover it after, in this case, batch developing five films :-(

...Sweep

190451

Andrew O'Neill
23-Apr-2019, 12:46
Did you mix up your developer with tap water? All my stock solutions are mixed with distilled water.

Sweep
23-Apr-2019, 12:56
Hi Andrew,
Yes, I did but always have done and have never had a problem until the last couple of batches. The water in Yorkshire is renowned for being very 'soft' so have always done it with tap water.
If it was mineral deposits in the water wouldn't it affect the whole negative surface not just the mid-greys?

NER
23-Apr-2019, 17:17
The most likely explanation is chemical dust, i.e., undissolved ID11 constituents, adhering to the negative for a period of time resulting in greater reduction of the affected areas. The dust occurs because of insufficient make-up water or because a component, e.g., the accelerator, falls out of solution due to low temperature and/or a loss of liquid volume. Although not readily apparent for different reasons, the problem is likely present across all values that make up the image. Dark spots like these may also be caused by water spray drying on the negatives, but the pattern seen here and fact that (1) this occurred twice with separate emulsions, and (2) that the same developer was used in both cases, points to chemical dust in the developer. More vigorous agitation would prevent the wayward constituent(s) from settling on the negatives but would also increase contrast to a degree that might be unwanted, so the best answer to your problem is to discard the used solution or, if you are going to use the same batch of developer, drive the dust back into solution using gentle heat and, as an added precaution, filter the developer after it reaches working temperature.

N. Riley
http://normanrileyphotography.com

Steven Ruttenberg
23-Apr-2019, 20:44
I had black spots/white spots when I was using PyrocatHD. As it turns out the developer was bad. Could be the developer is bad.

Andrew Tymon
24-Apr-2019, 04:44
Hey Sweep, so how much film had you put through the I'd-11? I'm taking it you reuse it rather than one shot. How old was it? I never liked those concertina bottles too many nooks and crannies for crap to hide in, plus they are type 2 plastic which is air permeable. I like to store solutions in type one plastic bottles, the type water and soda come in. How old was your fixer and do you monitor its through put? I wouldn't develop my 8x10s till I got this sorted either.

Sweep
24-Apr-2019, 12:06
Hi Guys,
You are probably correct about the developer being bad. Time does fly by and I hadn't marked the container as to when the mix was made; note for future!
I never reuse the developer and mix it 1:1 just before use, use it, and then ditch it.
I have only ever used ID11 and haven't previously had problems as my results have always been good. It is interesting, however, to read Norman's comments about low temperature storage as I do keep the dev kit it the basement and it has been pretty cold over winter. I never thought it would be bad for the developer as it is ideal for film storage.
I still have one 5litre box of ID11 on stock but might try liquid developers next time