Grain clumping, a controversial issue

[richard ide]

Interesting discussion.
I think that the term "grain clumping" is a bit of a misnomer because it implies something which is not caused by outside influence. I have intentionally reticulated film and observed the increased apparent graininess due to emulsion movement. Perhaps there are other words which could more accurately describe the phenomenon.

 

[Photo Engineer]

I am getting a LOT of PMs on this one!

PE

 

[Ray Rogers]

Thanks to Tim for pulling out the name of the English Major...
perhaps that Ph.D. was honorary?

Dr. Suess? The Grain in the Frame?

No wonder Ian concelled the source!

 

[Ian Grant]

Ray, I didn't cancel the source, and previously also linked to John Davies comments which are similar, and independent of Suesse. John is probably the leading European landscape photographers with work in a large number of collections around the world, including the US, he's also University course leader in Photography in Liverpool (UK). John is also part of an eminent circle of photographers who's views and practical skills I'd rate as second to none, and link back through workshops to Adams and Minor White.

The issues are that they write about a form of excessive grain that I've seen first hand with 120 Tmax 400 where the grain was so excessive it made the negatives unusable, while 35mm Tmax 400 negatives I processed in the same chemistry were fine grained as expected. The only difference being temperature control.

Attacking the credentials of writes in order to dismiss their statements in no way means their statements are wrong, after all Ansel Adams was a Pianist and the inventors of Kodachrome also musicians.

There's plenty of evidence out there that the issue exists, just try searching for posts about peoples problems about Neopan 400 & Tmax 300 and excessive grain

When it comes to grain clumping/micro reticulation I have to believe what I read in the original Darkroom Technique article back in the mid 1980's and my own & others experience.

Personally I don't find it odd that little is written about grain clumping/micro reticulation or whatever you call the excessive grain formed when films are subjected to temperature changes outside the normal recommended parameters.

What has been written is the detailed Darkroom techniques article on Micro reticulation in the 80's, unfortunately not available online, and then references in books and websites similar to Suesse's comments but independent. They can't all be dismissed out of hand.

Then we have numerous people who've posted their excessive grain issues here on APUG, their comments are being dismissed as well.

As to why it's been called Micro Reticulation, that's rather obvious and logical. It's what happens to a film that causes the excessive grain in the stages before full reticulation occurs.

Interesting discussion.
I think that the term "grain clumping" is a bit of a misnomer because it implies something which is not caused by outside influence. I have intentionally reticulated film and observed the increased apparent graininess due to emulsion movement. Perhaps there are other words which could more accurately describe the phenomenon.

Some do the same but not deliberately and that's what we are talking about here. All that's unknown is what temperature differential is sufficient to cause an increase in grain size.

Ian

 

[Mark Antony]

As to why it's been called Micro Reticulation, that's rather obvious and logical. It's what happens to a film that causes the excessive grain in the stages before full reticulation occurs.
Some do the same but not deliberately and that's what we are talking about here. All that's unknown is what temperature differential is sufficient to cause an increase in grain size.

Ian

Ian I'm not sure that you can catagorically state that any increase in apparent grain size is down to one single metric.
There are many reasons why film may exhibit grain. your micro-reticulation theories don't make logical sense.
In order for reticulation to occur the gelatin is ruptured and apears rather like crazy pavement under a microscope. The effect doesn't appear slowly and then build. In these days of hardened emulsions reticulation is hard to induce if micro reticulation exists then how come no text books actually mention it?
I have several papers here about emulsion problems none mention it.

Kodak have published quite a lot of information about graininess and granularity and none mention the effect, the latest information uses a very complex computer system to measure emulsion characteristics at levels which can't be observed by eyes-why haven't they seen this effect in the emulsion?
NB
Graininess
The appearence of uneven density in an image which occurs in the viewer.

Granularity
The measure of the frequency of actual grains measured with a microdensitometer over a given area.

 

[Ian Grant]

Mark, they aren't my Micro reticulation theories they were published way back in the mid 80's and I agree that there's more than one factor involved, I've always said that. However temperature shifts seem to be the trigger for excessive grain in many cases, but it's important to note that without these shifts then excessive grain with mainstream commercial film developer doesn't occur.

The fact's are that people are getting this excessive increase in grain and, despite people in this thread stating otherwise, they've posted about it on this forum and elsewhere. Text books do comment on the increased graininess with poor temperature control and also point out it can lead to full reticulation. It's the terminology which is causing confusion, not the issue itself but as it's related to reticulation it's apt.

Ian

 

[Tim Gray]

Attacking the credentials of writes in order to dismiss their statements in no way means their statements are wrong, after all Ansel Adams was a Pianist and the inventors of Kodachrome also musicians.

First of all, I have no dog in this fight.

Second of all, I wonder how much of this argument could be avoided if we stopped saying micro reticulation = grain clumping. Are they the same in people's minds? Are they two different things?

Two definitions from his quote:
statement = temperature control is very important to prevent graininess
explanation for statement =the increase in graininess is caused by micro reticulation

Third of all, I just want to be clear I wasn't attacking his credentials. His statement could very well be true - I don't know. What I do know is that he then goes on to give a pretty technical explanation why poor temperature control can lead to graininess. I am *assuming* (though I think it's a fair assumption given his credentials) that while that explanation *might* be applicable, he did not do the research to back up the explanations validity. He also gives no source for that explanation.

Just because other photographers experience increased graininess, short of full blown reticulation, due to poor temperature control DOES NOT mean that micro reticulation causes it. It means that they get an increase in apparent graininess. The micro reticulation hypothesis might be the correct hypothesis, but until someone actually does the research to prove that it is the (likely) cause, it's just a hypothesis. As a bystander to this whole argument, I have not seen a valid source of research presented showing that micro reticulation occurs in these conditions, or even occurs at all. That doesn't mean they don't exist; just that no one has offered one up yet. However, I do not see how 'prominent photographers' feel this is the correct explanation somehow scientifically validates this whole idea. All it says is that they see an increase in apparent graininess.

So again, to reiterate: temperature variations in processing may very well lead to increased apparent graininess in certain films without entering the zone of reticulation. However, that does not mean that this micro-reticulation hypothesis is the correct explanation. (Nor does it mean that it is wrong.) Without research to back that up, it's just a hypothesis.

 

[Ray Rogers]

Ian,

It really looked like you were avoiding being pinned down!


The one thing that really is missing here is hard visable evidence.

The examples which I have... could be posted (or sent to Kodak or someone independant) to make a study and comparison to traditional reticulation.

My own opinion is that perhaps the terms "silver" or "grain" do not even need to be invoked... the whole effect may be nothing more than regular reticulation, but one where the gelatins movment is serverly restricted, above and beyond what was once considered normal.

I don't know - on the other hand,
there was a strange fogginess I didn't recall seeing with regular reticulation.

I guess other people need to examine the evidence before much more of value can be said.

The fact that I am the only one who claims to have samples of this sort of reticulation worries me to no end though...

 

[Mark Antony]

Ian do you have an image with this 'micro reticualtion' as you call it?

I've never seen or heared of it, its not in any of the Journals or published data. Everything I have suggests reticualtion has a threashold, not that it slowly occurs
It would be good to see a microphotograph of the damaged gelatin. as current data seems to suggest reticulation occurs at a certain temperature threashold-not with small (under 5c) changes.
If not can you submit one for us to analyse?

 

[Ian Grant]

Thanks for clearing that up Tim.

I've stated clearly why I support the micro reticulation theory many times in numerous threads. I read the 80's article which made total sense, and it would be easy to prove with a film like Neopan 400 which is known to reticulate easily, the crux of the issue is that bonds in the gelatin are being broken long before actual reticulation, the cracking of the gelatin at the films surface takes place.

Ian

 

[Mark Antony]

Can't see it myself Ian. I think I'd need to see proof. You see 'gelatin being broken down befroe reticulation takes place' doesn't make sense.
It either reticulates or it doesn't that damage has a threashold, what you seem to suggest is that something happens before reticulation-this would be a new discovery.

There should be a micro-photo of this effect, someone should have spotted it over the last 80 years or so-colour me doubtful.
Sorry
mark

 

[Ian Grant]

Ian do you have an image with this 'micro reticualtion' as you call it?

I've never seen or heared of it, its not in any of the Journals or published data. Everything I have suggests reticualtion has a threashold, not that it slowly occurs
It would be good to see a microphotograph of the damaged gelatin. as current data seems to suggest reticulation occurs at a certain temperature threashold-not with small (under 5c) changes.
If not can you submit one for us to analyse?

I do have 3 sets of 120 Tmax400 negatives with micro reticulation/excessive grain, because the photographer who processed them left them in my darkroom after discovering just how bad the grain was. It'll be February/March now before I can send samples from those negatives to anyone, but I'm quite happy to do so.

Logically if the pressure of a film's gelatin expanding or shrinking creates physical surface cracking there has to be something happening to the gelatin layer during the build up to that threshold. There's a lot of stresses involved.

I have absolutely no doubts that the issues occur and why. However I can also understand why little is written on the subject, because it's probably extremely rare in commercial situations and experienced photographers, particularly those that write on the subject beacuse good process control, particularly of temperatures has always been stressed and advocated.

My own opinion is that perhaps the terms "silver" or "grain" do not even need to be invoked... the whole effect may be nothing more than regular reticulation, but one where the gelatins movment is serverly restricted, above and beyond what was once considered normal.

I don't know - on the other hand,
there was a strange fogginess I didn't recall seeing with regular reticulation.

I guess other people need to examine the evidence before much more of value can be said.

The fact that I am the only one who claims to have samples of this sort of reticulation worries me to no end though...

Ray in previous threads others have clearly stated they've had the same problems and that tighter temperature control prevented the problems recurring again.

The bit I've highlighted is similar to what the 80's article referred to as micro reticulation, it's the precursor to full reticulation.

I find it strange that people who've never seen the problem actually deny it happens.

Ian

 

[Ian Grant]

Don't assume all films behave the same, Ilford films are well harder in addition the type of developer and fixer will have an effect as well. So many current posted issues are with for instance Rodinal and Neopan 400, where it's probably not just the pH but the presence of Hydroxide that increases the potential for issues of excessive grain and many reported case of actual reticulation.

Ian

 

[Bruce Watson]

I don't need to give references to something I've seen first hand...

It all comes down to how science is performed, and the difference between fact, and belief. The scientific method is constructed to remove subjective belief from the discussion. When done correctly (and that's far from a given) all belief is removed and all that's left is fact.

The basis for this is published experiments. If someone else can replicate the results by repeating the published experiments, then it's more likely that the results can be view as fact.

This is probably why PE and others are looking for your references. They want to read about the experiments and the results, look for corroborating experiments, and perhaps to perform the experiments themselves for corroboration.

But I'm sure you already know that. I'm just posting for those that may be confused by this particular back-and-forth.

 

[Photo Engineer]

Tim, Mark, Bruce;

All very valid and good responses. You encompass much of what I have tried to express here. These "faults" will have to remain in the realm of hypothesis until repeated and examined carefully. Otherwise, there is no reputable documentation.

PE

 

[Ray Rogers]

I do have 3 sets of 120 Tmax400 negatives with micro reticulation/excessive grain, because the photographer who processed them left them in my darkroom after discovering just how bad the grain was. It'll be February/March now before I can send samples from those negatives to anyone, but I'm quite happy to do so.

Ray in previous threads others have clearly stated they've had the same problems and that tighter temperature control prevented the problems recurring again.

I find it strange that people who've never seen the problem actually deny it happens.

Ian

Ian,

We cannot judge by such claims;
They may or may not know what they are talking about.

I myself don't find it that hard to understand the doubters...
First a huge amount of study and research goes into products in the first place and this extends (perhaps indirectly) to abnormal processing, and secondly, photographers from all over the world may send in complaints to mfgs if they find anything to complain about... so it is strange that the MFG would be unaware of this issue.

Thirdly no one here has come up here with visual proof.
(btw, are there sample pictures (photomicrographs) in Mr. Suess's book?)

Since you still are without access to your samples, it seems like I might be the first to get around to actually posting example of what to me at least, seems to fall under the heading of "microreticulation".

If anyone wants to try to create these images,
the only thing I can offer as a hint
are my conditons:
TMax 400 in t-max dev. (probably 1:4 std dilution)
Acid stop, rapid fix,
temps pretty much normal
except for rinses and possibly a hypo clear session and
but the final wash...

That was a running water wash I tried to ballance
with hot and cold taps (without a themometer) to what "felt right".
As we all konw, that sense is easily tricked!
Presumably it went very cold.

(I say that because upon seeing the trouble
I did test the temp and it was as low as about 13 - 17 degrees C.)

So, summary: normal processing followed by a final cold shock...
(but w/ flucuations along the way)

 

[Photo Engineer]

BTW, for Tmax 100, Kodak gives a permissible process range of 65 - 85 degrees F for each solution and makes no mention of keeping the temperature constant throughout. The normal range is 65 - 75 F for tray and drum and up to 85 for machine processing.

Therefore, they allow this huge range with the provision that the correct development TIME be used for any given temperature. And, they mention no problems with reticulation of any sort. This has been my experience as well with both B&W and color products.

PE

 

[michaelbsc]

I think it us important that people understand that the statement \"There is no scientific evidence for X\" is not an implication that X is or is no true. It is an expression that no verified statement can be made.



As one who has worked in a lab environment in the past it is often clear that many people do not hear that distinction even though they know it intuitively.



I, for one, agree with a previous poster that what we need more than anything else in this discussion is an agreed set of definitions.

 

[Ian Grant]

Interestingly Kodak DON'T recommend 80ºF/27ºC or 85ºC/29ºC for Tmax 100 & 400, but they do for P3200, that indicates there must be a difference in hardening between the P3200 and the other two films.

The issues we are talking about typically occur outside that 18º-24ºC range, usually when temperatures subsequent to development are lower, often significantly. Elsewhere Kodak like Ilford actually recommend keeping the temperature difference between baths to +/- 2ºC which is fairly typical darkroom practice anyway.

Ian

 

[Mark Antony]

Ian
reticulation is defined as the lateral movement of the gelatin with respect to the base, in other words it is a mechanical defect caused by temperature 'shock' it has no effect on the grain size per se it is a getalin/base interface defect.

What you need to prove is that relatively small (within the parameters of published temps say 18-40°c) temperature changes cause smaller fissures to occur between the base and the gelatin, proportional to temperature.

All current data suggests that this occurs to the gelatin/base interface at quite high temperatures nominally over 50°c with T Max films. What you also have to ask yourself is why with a modern hardened and plasticised film this effect should be noted, when all the books published before that time make no mention of reticulation at such small levels giving apparent increase in perceived grain.
Mark

 

[Photo Engineer]

Interestingly Kodak DON'T recommend 80ºF/27ºC or 85ºC/29ºC for Tmax 100 & 400, but they do for P3200, that indicates there must be a difference in hardening between the P3200 and the other two films.

The issues we are talking about typically occur outside that 18º-24ºC range, usually when temperatures subsequent to development are lower, often significantly. Elsewhere Kodak like Ilford actually recommend keeping the temperature difference between baths to +/- 2ºC which is fairly typical darkroom practice anyway.

Ian

Please see page 23 here: http://www.kodak.com/global/en/professional/support/techPubs/f4016/f4016.pdf

See also page 27!

Versamat processing includes development at 80 and washing at 70 - 75 degrees which is up to a 10 degree F change from the fixer!

PE

 

[Jerevan]

Come on, guys, give it a break now, huh? This is the worst, ill-defined and mummy-ridden mess since the Fixer Wars.

 

[Ian Grant]

Mark, it's not a case of me proving anything. Why prove to myself something I've already seen proof of first hand. I've also stated that I'm quite prepared to send some of the negatives to Greg Davis earlier in the thread.

I'm well aware what reticulation is, I worked as a photo chemist in the 70's & 80's and have more than enough experience of all types of B&W film & paper processing issues.

As I've stated before some of the films which show the greatest problems Tmax 400 & Neopan 400 seem according to others to be worst in certain developers, Rodinal being one example.

Now is every manufacturer run tests of their films with all the developers from rival film manufacturers and the whole gamut of 3rd party chemistry ? And then test each to see at what point garin increases or reticulation occurs with temperature deviations, it just wouldn't even be contemplated, particularly when there's no problems whatsoever when chemistry is kept within a reasonable temperature range typically +/- 2ºC.

It's also a false assumption to think that the issues aren't covered somewhere in research disclosers or Patents, it's more that it's impossible to search the many thousands of documents published in the past 40 or 50 years.

I will try reproducing the excessive grain issue again with some old film stock I have in a drawer, but there a number of variables, and it's knowing at what stage it's most likely to happen. There's a post been lost from this thread when the site went down yesterday morning (GMT) where someone said they'd processed a Tmax film deliberately trying to get reticulation and got excessive grain instead.

Ian

 

[Ian Grant]

Please see page 23 here: http://www.kodak.com/global/en/professional/support/techPubs/f4016/f4016.pdf

See also page 27!

Versamat processing includes development at 80 and washing at 70 - 75 degrees which is up to a 10 degree F change from the fixer!

Ron, re-read my post, because page 23 does not cover Tmax 100 & 400 at all, the data is specific to P3200 only.

So your comments are rather irrelevant, none of the people getting these issues own a Versamat or similar, and the chemistry is specifically designed for higher temperature processing.

So it's yet another red herring.

Ian

 

[Photo Engineer]

Ian;

Please see my references above to the Kodak web site for the temperature recommendations for processing T-max 100. The data for other films are easily read from that point. It is inconceivable to me that Kodak would recommend such a large temperature range and possible abrupt temperature changes if this problem existed! In fact, to prove to themselves that this works, some guy at Kodak ran all of those time and temperature combinations with all of those developers to assure quality. The tests included sensitometry, grain and sharpness measurements with different process times as well, and surely would have shown up a problem such as is under discussion here with the various films.

And, Kodak does test their films and papers with developers from other manufacturers. In fact, the tests by Ross in the OP used 16 developers including Rodinal! Kodak also tests other manufacturers films and papers to insure continued compatibility with their own recommended process conditions.

The amount of data collected and the amount of work involved constructing such a web page is truly huge. It is carefully analyzed by several people and some experiments are repeated many times to insure accuracy in reporting. Each time line on the developer chart represents about 1 roll of film used, and each temperature multiplies that number as does each of the other variations, and that is just to get the sensitometric curves to report contrast, fog and speed. And you think they are going to cover something up with that broad range of conditions? You have to be kidding yourself.

PE