Negative quality

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You probably all have those moments when you want to smash something, today is one of mine. Lately my negatives (6 x 6 medium format) are grainy. I know my camera is capable of being sharp, (Mamiya 330S and Hasselblad 501 CM). The pictures are sharp at 5 X 5 but really are not worth enlarging beyond that. Using XTOL 1:3 and Ilford FP4 film. Always use distilled water, at 68 degrees. I know it's not my enlarger, I eliminated that with some older negs, printed just fine.

I can see by examining the negative that the focus point is on the subject, but the detail is fuzzy. I have an older book that says reticulation can be caused by tempeture variations, (how much) and overused fixer (is that true?). I am on well water were I live, and the temp is usually four or five degrees of the develop temp. (68),I rinse the film in this water, then back into distilled water for a final rinse. (BTW, using small tank, invert 10sec./per min. for 16 mins.)

I have tried rating FP4 at 125, 64, 32. Seems like the quality goes up with the lower ISO. I compensate by shortening the developing time. Has any one experienced this? Any suggestions?

-- John Clark (john.e.clark@mindspring.com), February 08, 2000

Answers

In an old book (dating from the late sixties) I read that to intentionally cause reticulation, you should develop the film in "hot" developer (I think suggested a temperature of over 30 degrees Celsius.) and wash in cold water after developing. There was also a warning that this might happen unintentionally if the temperature mismatch between the baths were too big. The effect is explained as owing to the different thermal expansions of the film base and the gelatin, and I always thought that it is not a very likely thing to occur with today's films which have very thin emulsions. Yet, maybe this is what happened.

-- Thomas Wollstein (thomas_wollstein@web.de), February 08, 2000.

John, Look at the negatives under a 10X or so magnifier. Reticulation clumping usually looks quite different from large grain. If your solutions only vary by about 5deg F, most film won't reticulate. If the only cool solution is the final wash, it is less likely to be reticulation. Hot developer and cold wash before fixing will give you reticulation. Sometimes you can get it with cold fixer. When I did it on purpose, I used larger temperature differences, even for moderate reticulation.

-- Richard Newman (rnewman@snip.net), February 08, 2000.

I agree it is unlikely to be reticulation, within 4-5 deg F, but I suggest you get all the fluid (dev, stop, fix, wash) to the same temperature (within 1 deg F) just in case. Leaving the chemicals and a bucket of water overnight in a room at that temperature should do the trick.

Overused fixer causes underfixed negatives, which is far worse than mere reticulation. Some peopled in this forum have said that hardener in the fixer will reduce the chances of reticulation.

Genuine grain is proportional to developing time, and if the results are better with less development, then that is what it is. You might prefer a finer grain developer, such as Microphen. Or a finer grain film, such as Pan F+, or Delta 100 or T-Max 100.

Grain is more noticable on areas with no detail, such as out-of-focus areas. So another 'cure' is to ensure your pictures contain no out-of- focus areas.

-- Alan Gibson (Alan@snibgo.com), February 08, 2000.


I mix water in a relatively large vessel to working temp (+/- 2 deg. F) for rinsing rather than depend on temp out of the tap. Reducing dev. time does reduce grain but then you need higher contrast paper, which brings the grain back up, in my experience. Overexposing traditional B&W increases grain and reduces sharpness. Just enough exposure for the shadows does the trick. I use Xtol and Microphen, both diluted 1+2. Microphen gives more grain and shadow speed in my darkroom.

-- Tim Brown (brownt@ase.com), February 08, 2000.

Have you tried mixing another batch of XTOL or using FP4 with a different emulsion number? I'm a guy who also shoots a 'Blad and loves that film and developer combination--I'm afraid I just "gushed" about it in another post--so, like you say, we know the combo can work.

All I can think of is using bad XTOL, maybe some where Part A was caked, or bad film. I had some Agfa 25 once where the emulsion flaked off in big chunks, and I'm sure Agfa isn't the only manufacturer to have quality control problems once in a while.

When you do find out, would you post what you learned?

-- Brian Hinther (BrianH@sd314.k12.id.us), February 08, 2000.



Recirculation has a very distinct look about it and will look like a pattern, quite different from chunky grain. I had some Konica IR750 'recirculate' (is that a word?) but the FP4 in the tank at the same time showed no effect. I think mine was caused by a hot wash as I use all temp adjusted devl/stop/fix but my wash is straight from a 'mixer' tap and on this occasion although it started at 20C it varied on it's own accord to much hotter. This was the first (and only -I know check the wash temp) film that I've had do this and it fooled me since the FP4 showed no effect.

-- Nigel Smith (nlandgl@eisa.net.au), February 10, 2000.

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