Strange fogging on B&W

[jeff_ford]

I recently became so fed up with the appaling B&W developing

services locally available to me, I decided to go back to doing my

own.

 

I bought a Kaiser 4297 twin 35mm spool tank and processed 2 rolls of

FP4, each shot on a different camera.

 

Both rolls had the fogging shown below - I've never seen fogging

like this that didn't go accross the perfs - light leak in the tank?

 

Opinions gratefully received

[jeff_ford]

Forgot to mention the image is obviously from the end of the roll where there were no images - just to make the problem clearer.

[brian_e]

hmmm that looks suspiciously like over-agitation, anyone else think so?

[silent1]

I'd have to see a shot in reflected light to be sure, but it appears the film is properly developed and fixed at the edges, but dense in the center, with a fuzzy edge and flow marks from the sprocket holes. If that dense area looks milky, it's because your fixer was exhausted -- incorrectly diluted, perhaps, or made from very old stock -- or the film wasn't fixed anything like long enough; you've got more clearing in the edges, where more solution could reach the film surface, than in the center. If that's the case, you can most likely salvage the negatives with only a very slight residual fog (from printing-out) by refixing in fresh fixer.

[helenbach]

Could you tell us more about the process: developer, fixer, dilutions, times etc. Does the fog look like developed silver or partially cleared, undeveloped emulsion? I would discount a light leak and guess at a fixing problem - too little agitation and too little time.

 

Best, Helen

[jeff_ford]

FP4 was processed in ID11 BUT fixer used was something called Fotospeed FX20 rapid fixer diluted 1:9 it was left in the tank after agitation for about 3 minutes (no stop bath was used by the way....)

 

The recommended time is one minute.

 

As to whether its "developed silver or partially cleared, undeveloped emulsion" Helen, I wouldn't have a clue. It seemed to me like 'on spiral' fogging due to where it drops off, though I hadn't considered your fixer theory. I have no idea if these things have a shelf life as I cant see a sell by date. It was however only bought a week agao and was mixed 10 minutes prior to use.

 

 

Intersted why somebody thought over agitation was to blame???

 

Appreciate the help

[jimvanson]

The light streaks moving toward mid-frame from the sprocket holes could look like an agitation problem but I don't believe either that nor the fix is the main problem. (Especially the fix as the edge data is fairly clear).<P>And so what the hell is happening? Beats me but it certainly is interesting.<P>Is the Kaiser a plastic tank? Does it have a plastic post that the reels slip onto. Is the post being used?

[ronald_moravec1]

Your fixer is either used up, not mixed strong enough or most probably UNDER agitated. Invert and roll in the fixer. You can`t agitate too much. I invert 5 sec each 30 and several time during the fix cycle roll one way and then the other.

 

cut a small piece off the pictured section and soak in the fixer with agitation. If it clears to film base, rewet the film, refix, and wash. I don`t think you hurt it.

[ronald_moravec1]

If the test didn`t clear the film, remix new fixer checking the instructions again and repeat test. It should clear in two min max.

[ronald_moravec1]

Once again- do not fill the tank with developer or fixer. Use only enough to cover the reel plus a little. The liquid must have a place to move when you agitate. Take the cover off and measure the amount if nesessary.

[jay_de_fehr]

Looks like the developer surged through the sprocket holes to me. Try gentler agitation in your developer and see if that solves the problem.

[silent1]

<i>FP4 was processed in ID11 BUT fixer used was something called Fotospeed FX20 rapid fixer diluted 1:9 it was left in the tank after agitation for about 3 minutes (no stop bath was used by the way....)<p>

 

The recommended time is one minute.</i><p>

 

And there's your problem. Rapid fixers can only be so strong (the concentrate is mostly 60% ammonium thiosulfate solution, after all); a 1:9 dilution is paper strength, and a one minute fixing time is paper time. Refix ASAP, using 1:4, for at least two minutes (I generally give three to five), agitating as you would during development (Kodak actually recommends continuous agitation during fixing, but I haven't found this to be necessary).

[alessandro serrao]

It's not a fixer problem: if it was the case the very edges of film should reveal some density, because it's where the fixer solution move the least. Instead the edges are crystal clear. So, to narrow down the problem you shoud try to develop another Fp4 using another thank (preferably new) using as fresh chemicals as possible.

Use double the time it requires the film to clear in a fresh mixed fixer solution (should it be rapid or normal, it doesn't matter).

Better yet use a double fixing bath technique, very effective in removing the anti-halo layer also.

[ronald_moravec1]

Please read my three answers AGAIN, now we at least agree it is a fixer problem. I never used fotspeed fix, but I did tell you to reread the instructions. MY first comment was the fix may not be strong enough and there is definately a lack of agitation.

 

I have seen this in my darkroom, and it traces back to the three causes I mentioned.

[kevin_chan1]

<p>

I had a similar problem with fogged-up negatives recently. Here's my post:<br>

<a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=008Wvu">Need

help on mysterious fogging problem on my negatives</a>

</p>

 

<p>

The fogging problem on my negatives didn't look as severe as the one in your pic, but with

the help of all the folks who answered my posting I found that my problem was in fact

insufficient fixing. A quick rinse in a tray of fixer and all the negatives cleared

up.

</p>

 

<p>

I don't know if you're having the same problem I had, but I would second all the people

who suggested re-fixing the negatives.

</p>

 

<p>

-Kevin

</p>

[jeff_ford]

It was insufficient fixing. I resoaked for 10 minutes, went back to the negs and they were crystal clear.

 

This is odd as I'm convinced that i followed the instructions to the letter. Could it be a flow problem inside the tank?

 

One further observation. When you think your negs are gone forever, weren't they just the best negs you've ever shot? Now with your help I've saved them..... they look so ordinary!

 

Many thanks everyone.

[jeff_ford]

Just as a last thought - is it possible to over fix?

[chris_eve]

Apparently it is theoretically possible to "over-fix", the acid component in the fixer will eventually start to dissolve the silver. This'll obviously first show in loss of shadow detail.

 

Many years ago I did try using "non-rapid" fixer as a reducing agent for a dense negative, mostly 'cos it was all I had to hand, but couldn't see any significant difference after 30 minutes in film-dilution fixer, (again, all I had to hand), so gave up. If you really want to know, take a couple of identical negs and soak one in undiluted fix for a period. Once you can see a difference you can reasonably assume that about 4x that time would be how long it would take for normal dilution fixer to have the same effect.

[silent1]

I've recently done a very slow, very slight intentional bleaching of negatives using film strength rapid fixer (1:4 from concentrate, Ilford Rapid Fixer), acidified with one ounce of stop bath concentrate (effectively 28% acetic acid) per eight ounces of fixer -- obviously, I didn't return the fixer to the bottle after adding the stop bath. The additional acidity did lead to a discernible reduction in density over about an hour of soaking with occasional agitation -- as it turned out, this batch of negatives couldn't be saved, but with "normal" negatives I'd probably have seen significant loss of shadow detail in much less time than an hour.

 

With ordinary acid fixer at film strength, there's no visible change in an hour, though it's probably possible to measure loss of shadow density over that time frame if you have a densitomer. With alkaline fixer like TF-4, there is reported to be no bleaching action at all -- or at least any bleaching is so slow as not to be of concern. I certainly wouldn't worry about fixing 2-3 times the recommended interval in ordinary film strength fixer -- ten minutes, for instance, where three is indicated by the clearing time.