Grain clumping, a controversial issue

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OP
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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

Ian;

See page 6 and 7 for the 100 and 400 films. They use 65 - 75 degrees there for most developers. And the fact that a Versamat can be used at higher temperatures without a problem is beside the point. It can be done at higher temperatures with in-spec results.

Not another red herring, I just gave the wrong page.

PE
 

Ian Grant

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Your poste getting irrelevant now Ron, and are just deliberate attack,you clearly didn't read F-4016 the Kodak PDF properly as page 23 does not refer to either Tmax 100 or 400.

In addition while I'm sure that Kodak test their films in rivals products and vice versa I very much doubt they'd do any testing outside normal processing parameters, otherwise where do you stop.

None of your posts now address the issues of excessive grain/micro reticulation/grain clumping with temperature deviations.

Ian
 

Ian Grant

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Ian;

See page 6 and 7 for the 100 and 400 films. They use 65 - 75 degrees there for most developers. And the fact that a Versamat can be used at higher temperatures without a problem is beside the point. It can be done at higher temperatures with in-spec results.

Not another red herring, I just gave the wrong page.

PE

That's what I already said in my Post, so it really is another RED HERRING, why don't you just stop. I took the figures from the same data-sheet.

These post of yours are now just deliberate personal attacks.

Ian
 

Mark Antony

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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.
Ian

Ian if you're well aware of what reticulation is then why introduce the red herring of the developer type?

Reticulation is the lateral movement of the gelatin separating it from the base, the developer type has no bearing on that, it is a temperature shock that produces reticulation by expanding the gelatin so that is moves away from the base.

If you are seeing a difference in perceived grain with different developer temperature combinations then that is entirely a different physical occurance.

Increase or change in grain size is not related to reticulation one is a gelatine/base interface problem the other is crystal growth and or morphing of crystal shapes due to temperature or agitation etc.
It has been noted by many studies that Rodinal gives more grain at higher temperatures, this is not due to reticulation.
 

Ian Grant

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Ian if you're well aware of what reticulation is then why introduce the red herring of the developer type?

Because developer type is a factor which come into play, hydroxide softens gelatin.

If you are seeing a difference in perceived grain with different developer temperature combinations then that is entirely a different physical occurance.

In the summer I process at 26º-27ºC and see no difference between those my UK 20ºC negatives even with 35mm and I agree with Ron's data on this as well.


It has been noted by many studies that Rodinal gives more grain at higher temperatures, this is not due to reticulation.

It's not down to developer temperature either, but it may be down to variations in the temperatures of the rest of the process cycle.


Increase or change in grain size is not related to reticulation one is a gelatine/base interface problem the other is crystal growth and or morphing of crystal shapes due to temperature or agitation etc.

That's the crux of the issue, and where you may be wrong as it's not developer related in terms of the actual development part ot the process itself, because it happens afterwards.

Excessive temperature changes (and pH) affect the swelling and shrinkage of gelatin, and choice of developer can come into play as well. But these affect the gelatin (or polymer) so may well be related to reticulation as the 80's article claimed.

Ian
 
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Gentlemen;

Both acid and base can soften bone gelatin, but base will swell bone gelatin and acid will shrink bone gelatin. Faster films have higher iodide, larger grains and are generally coated thicker than slower films so as to capture more light. Highly swollen gelatin allows photographic reactions (development and fixing) to take place more rapidly. Excess hydroxide also speeds most development reactions. These factors influence all process recommendations to an extent.

However, the Kodak PDF file does show us a permissible temperature range for processing the Tmax family and that range is from 68 to 75 degrees not counting the Versamat which can be used at up to 85 degrees. The PDF also shows the maximum temperature change at one time going from one solution to the next. Although the data are not presented clearly, it appears that one can introduce a change of up to 10 degrees F going from one bath to the next or 65 - 75 deg F.

So, this is not a red herring, but rather goes directly to the point that Kodak did the experiments to prove that these conditions were acceptable for the entire Tmax family, and that adhering to these conditions, one should not expect anything out of the ordinary. Taken together, pages 6, 7, 8 etc and then 23 show the data for the entire family.

PE
 

Mark Antony

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Because developer type is a factor which come into play, hydroxide softens gelatin.



In the summer I process at 26º-27ºC and see no difference between those my UK 20ºC negatives even with 35mm and I agree with Ron's data on this as well.




It's not down to developer temperature either, but it may be down to variations in the temperatures of the rest of the process cycle.




That's the crux of the issue, and where you may be wrong as it's not developer related in terms of the actual development part ot the process itself, because it happens afterwards.

Excessive temperature changes (and pH) affect the swelling and shrinkage of gelatin, and choice of developer can come into play as well. But these affect the gelatin (or polymer) so may well be related to reticulation as the 80's article claimed.

Ian

Lots of different substances soften gelatin, even water but that does NOT mean that they are the sole cause (or even a contributory factor) of reticulation, which is a magnitude greater than the softening action of hydroxide, we are talking about the massive rupture of the gelatin away from the base-you claim by small temperature changes (I dispute this)

Variations in temperature, agitation and solution strength certainly do have an effect on grain size, and perceived graininess- much greater than anything you describe.
The 80's article you keep quoting sounds more and more far fetched as the thread goes on, micro reticulation would simply be reticulation at a lower level (which we know from countless studies doesn't happen as reticulation has a threashold)
Reticulation is a very definite lateral movement (not just swelling which moves in another plain) literally ripping the emulsion from the base and the gelatin then deforms.
This either happens because of large temperature differences between solutions or sometimes if the developer alone is hot enough to make the gelatine expand laterally faster than the base thus breaking the bond between the two.

Reticulation by definition is a high temperature issue, not one that manifests itself at a lower temps or even with different developers-Rodinal is no more likely to cause reticulation than any other solution because its temperature not chemical formulae which causes the massive disruption we call reticulation.
 
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Ray Rogers

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Do I recall correctly that reticulation has different appearences?
I seem to recall that the exact "look" one got was sort of up to the reticulation "gods",
perhaps like fngerprints or snowflakes, each had a unique "footprint".

It has been many years, but that is my recollection.
 

dwross

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

Nice try. Thank you for being brave enough to step into this dog fight. But, I think it would take a water hose to get their attention. They're having too much fun. The rest of us, maybe not so much.
 
OP
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The research through all of the texts and articles and the internet search was tedious to say the least. The continuing back and forth is as well. So, it is not really fun for me either. I am trying to invoke or evoke (your choice here) a critical look at this subject in order to prevent the possible creation or should I say perpetuation of another myth in the field of analog photography. After some tests are run that are done under controlled conditions, perhaps we will all understand this.

In the meantime, Mark Antony, among others, has expressed himself on this subject very clearly. Skepticism is in order here until some sort of understanding can be gained. I'm sorry that the intervening back and forth is not to your liking, but the results will perhaps lead to a better understanding for us all.

PE
 

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I find it all both educational and entertaining...no one has to click on the thread and read it.
 

Ian Grant

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Lets clarify a few points:

1. The temperature of the developer itself has little effect on grain size assuming development times are adjusted to compensate.

2. Processing a film within certain temperature constraints (variations) suggested by a manufacturer for the full cycle - Dev/Stop/Fix/Wash - and following the manufacturers recommendations should always give results they deem acceptable. That's not the same as the highest possible quality from that combination.


The next question is what are the manufacturers recommended temperature tolerances. The Kodak PDF/Datasheet (F-4016 - October 2007) for Tmax films gives development times for Tmax 100 & 400 for temperatures between 18ºC and 24ºC* and clearly states that stop, fix and wash should be within the same range. What they don't do is state what temperature difference between steps is acceptable, in fact they leave it very ambiguous.

* Disregarding Versamat processing as the Kodak developer (Duraflof RT) contains a hardener which allows processing Tmax 100 & 400 at higher temperatures. (Kodak - Duraflo RT - This developer features a hardener to prevent emulsion damage in the first developer tank of a roller-transport processor. Notice: Observe precautionary information on product).

However in a B&W processes trouble shooting guide Kodak state clearly “To avoid problems, use a consistent temperature for all your processing solutions. Select a temperature that you can maintain consistently”

John Sexton who worked closely with Kodak on Tmax films says quite clearly:
DO NOT USE T-MAX IF YOU ARE NOT CONSISTENT IN YOUR PROCESSING PROCEDURES. You MUST have repeatable work habits and procedures. Be concerned about 1 degree changes in developing temperatures. Process the film as carefully as you would color films, and you will get totally repeatable results. T-MAX films will teach you to improve your processing technique for repeatable results.

Ilford state that for best results it is recommended that all process solutions are kept at the same temperature or at least within 5ºC (9ºF) of the developer. (From their powder developer data-sheet).

______________________________________________________


However this takes us back to what I wrote in another Thread on this forum:

This is what John Davies has to say on the subject. John is Britain's top landscape photographer, his print quality from 120 films is 2nd to none, it's outstanding.

"It is also important to control the temperature of all the chemicals during processing and including the final wash. Slight fluctuations in temperature between the solutions will result in slight reticulation which is where the silver halide crystals form larger crystals to give the appearance of larger grain. Greater temperature fluctuations between solutions will result in a greater size of grain. In extreme cases the silver halide crystals form dominant textured patterns"


Here's the link to his website.


Now John Davies is a very level headed uncontroversial figure so now look again at Bernard Susse's comments:

"The temperature of all the solutions, including the wash water. Is critical be- cause of the danger of reticulation. Reticulation occurs when the film emulsion cracks. The emulsion swells and softens during processing. The warmer the temperature the greater the swelling. If the temperature drops quickly, the surface of the emulsion contracts while below the surface it remains swelled. This causes small cracks to appear ln the surface. The cracks can appear as a pattern throughout the image when a print is made. Occasionally this pattern can make an interesting image; usually it`s a distraction. A mild form of reticulation, known as grain clumping, can also take place. This makes the image appear grainier and coarser than it normally would with proper processing. This is the major reason to constantly control the temperatures of all solutions."


And then you'll find that the teaching notes of most US photography modules at Degree level contain something like this (Hawaii.edu):

Ideally, chemical solutions including wash water should be consistent in temperature, preferably at 68°F. (20°C). Temperature variations of +/- 5°F (2.75°C) are tolerated though grain size may be affected.


These are not isolated comments by any means, and lets look again at that Ilford recommendation - that all process solutions are kept at the same temperature or at least within 5ºC (9ºF) of the developer.

That puts Kodak's 18°-24°C into a similar perspective, when you add their comment that “To avoid problems, use a consistent temperature for all your processing solutions. Select a temperature that you can maintain consistently” that's a clear statement from all that a consistent temperature throughout the whole cycle dev/stop/fix/wash is the ideal.

___________________________________________


In practice there's plenty of visual evidence that photographers (& labs/technicians) who process with tight temperature controls get consistently better results than those who don't and let things drift up to 5°C or 6°C between steps.

The differences are seen in consistent high quality, good control of grain, as opposed to average quality, often unexpected grain, but still within manufacturers expectations. (Assuming same film/developer etc). While these improvements may be slight with 35mm it can be enough to make a noticeable visual difference when it come to print quality over 10”x8”,

So at one end we have a situation where good temperature control can help ensure finer grain, and as a consequence better tones & sharpness. This approach has been taught in colleges/universities & workshops for well over 25 years. Perhaps even more emphasis was placed on it before most films were better hardened.


Then we have the other extreme where big differences between process step temperatures will cause full reticulation with some films, and/or excessive grain with modern better hardened films.


So if we get slight differences in grain with small temperature variations +/- 5°C, and excessive grain at the other extreme +/- 10°C or even 15°C then it's logical that the greater the deviation between baths the more grain perceived in the negatives/prints.

There are other variables, because the pH and type of developer used, pH and type of stop bath or water rinse, pH and type of fixer will all have an effect on the swell of the emulsion and in some cases hardening or softening, and can in their own ways have an effect on the final negative qualities where temperature deviations occur.

Whether you call it Micro reticulation, Slight reticulation, a Mild form of Reticulation, Excessive grain or Grain clumping makes no difference.

The controversial part of this thread (and previous) is that people try to deny this, and the mid 80's Darkroom Technique article on Micro Reticulation showed the effects based on practical testing.

Ian
 
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Ray Rogers

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John Davies:
"Slight fluctuations in temperature between the solutions will result in slight reticulation which is where the silver halide crystals form larger crystals to give the appearance of larger grain. Greater temperature fluctuations between solutions will result in a greater size of grain. In extreme cases the silver halide crystals form dominant textured patterns"


Bernard Susse:
"Reticulation occurs when the film emulsion cracks. The emulsion swells and softens during processing... If the temperature drops quickly, the surface of the emulsion contracts while below the surface it remains swelled. This causes small cracks to appear ln the surface. The cracks can appear as a pattern throughout the image when a print is made. Occasionally this pattern can make an interesting image; usually it`s a distraction. A mild form of reticulation, known as grain clumping, can also take place. This makes the image appear grainier and coarser than it normally would with proper processing. This is the major reason to constantly control the temperatures of all solutions."

(Hawaii.edu):
Temperature variations of +/- 5°F (2.75°C) are tolerated though grain size may be affected.

Whether you call it Micro reticulation, Slight reticulation, a Mild form of Reticulation, Excessive grain or Grain clumping makes no difference.

Ian

Ian,

Lets all have a look at that Darkroom article...
and, see if Mr. Susse provides any photographic samples for us.

(Can someone provide the refs or scans of the needed material?)

As far as the "grain growth" described by John Davies - it just sounds wrong.

"silver halide crystals form larger crystals to give the appearance of larger grain."

After development, the only "silver halide" that is producing image silver has already been developed and thus no longer exists to form larger looking grains later on.

Being a stunning photographer doesn't mean he is able to describe accurately the things of photographic science. I think the concept of "grain" in an image is much too complicated to be done by casual observation. Not that it can't be done, but for anyone to make dogmatic statements about "grain growth", they absolutely need to actually be making measurements and not simply "eyeballing" it.

Bernard Susse's comments about reticulation proper are interesting perhaps even perceptive, but what visual evidence does he offer to suppport his words on "grain clumping"?

Tim?

The English terms may be inaccurately used
even if there is some substance to the phenomenon.
This is why I think we should avoid those terms until measurements
have been made.

Without actual grain size measurements, I must disregard (or regard with caution) all comments by any photographer, teacher or professor about grain size and processing.

The examples I made had the appearence of being
"grainy" and "slightly reticulated"
but I don't think I could say the grains had clumped
nor that they were larger in actual size.
 
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Mark Antony

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Ian
most of what you state is either false or debatable here is something that are obviously in error.

"Slight fluctuations in temperature between the solutions will result in slight reticulation which is where the silver halide crystals form larger crystals to give the appearance of larger grain".

Slight reticulation is where silver halide crystals form larger crystals?

By definition that's wrong.
Because Reticulation affects the gelatin.
Larger crystals are nothing to do with reticulation, because they sit in the gelatin.

The size of crystals formed is governed by many different parameters temperature is certainly one as is agitation and p.h also the vigour of the initial development etc.

One thing is for sure is that reticulation does not equal physically larger grain!
 

Ian Grant

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I guess I disregard some comments in this thread in the same way, basically because unless the writer's seen it for themselves they aren't in a position to really be objective. I don't get to hung up on John Davies description of the grain growth because the graininess does increase.

Over the years I've seen the really excessive grain that many describe first hand (as I've said earlier in the thread), but I've also also seen and helped people who kept having grainy negatives, unrelated to exposure and development time, and it's always been related to temperature controls, and I've seen a noticeably difference / improvement when I tightened up my own temperature controls. What I've seen just mirrors what I remember of the the magazine article.

Anyone can easily test the basic improvements gained tighter temperature controls for themselves, and there are posts in threads on this Forum by people who've done just that and had a noticeable improvement.

David Kilpatrick a photographer and writer has mentioned Micro reticulation in the past in magazine articles, he wrote for Camera or Phototechnique (both UK) then edited a couple of other magazines. He described Micro reticulation as causing excessive grain clumping, without a visible reticulation pattern.

Don't forget that the people who will see micro reticulation most are those teaching film based photography, and usually when students process shoddily, so it's noco-incidence they are writing about it.

Ian
 
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Ian Grant

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Ian
most of what you state is either false or debatable here is something that are obviously in error.

"Slight fluctuations in temperature between the solutions will result in slight reticulation which is where the silver halide crystals form larger crystals to give the appearance of larger grain".

Slight reticulation is where silver halide crystals form larger crystals?

By definition that's wrong.
Because Reticulation affects the gelatin.
Larger crystals are nothing to do with reticulation, because they sit in the gelatin.

The size of crystals formed is governed by many different parameters temperature is certainly one as is agitation and p.h also the vigour of the initial development etc.

One thing is for sure is that reticulation does not equal physically larger grain!


Nothing I've stated is false, what would be the point ? The quoted text can all be found elsewhere.

By your definition they may be wrong but the whole point is it's a gelatin related issue because it's not happening during development itself but ina or between subsequent steps..

The fact that the visual impact of excessive temperature shifts is often increased grain needs to be explained. The visual effect is called Grain clumping.

Ian
 
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Mark Antony

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"Don't forget that the people who will see micro reticulation most are those teaching film based photography"

Hey that's my job and I've never seen it! Let alone while I ran a lab with constant mains water fed system-you think in 22 years I'd have seen it!

If it is a gelatin issue how is it increasing grain size? BTW its not my definition but the agreed scientific definition of reticulation.
OK I can see the 'graininess' would be a problem if grain clumping or micro reticulation existed (which no one has proved)

"The fact that the visual impact of excessive temperature shifts is often increased grain needs to be explained. The visual effect is called Grain clumping."

Very reasonable, but not what you are arguing is it? Excessive temperature shifts will cause reticulation what you have been arguing is that very small difference between solutions will cause minor lateral disruption of the gelatin (AKA reticulation).
No current published research supports that, let alone 'massive' increases in grain brought about by minor ±5°c temperature shifts
 
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Ian Grant

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"Don't forget that the people who will see micro reticulation most are those teaching film based photography"

Hey that's my job and I've never seen it! Let alone while I ran a lab with constant mains water fed system-you think in 22 years I'd have seen it!

If it is a gelatin issue how is it increasing grain size? BTW its not my definition but the agreed scientific definition of reticulation.
OK I can see the 'graininess' would be a problem if grain clumping or micro reticulation existed (which no one has proved)

"The fact that the visual impact of excessive temperature shifts is often increased grain needs to be explained. The visual effect is called Grain clumping."

Very reasonable, but not what you are arguing is it? Excessive temperature shifts will cause reticulation what you have been arguing is that very small difference between solutions will cause minor lateral disruption of the gelatin (AKA reticulation).
No current published research supports that, let alone 'massive' increases in grain brought about by minor ±5°c temperature shifts


Mark, how can you be so sure you haven't seen it ? I'd be surprised if you've not seen students with negatives grainier than you'd expect. But they may be careful enough.

Here's another description -“microreticulation” that LOOKS like excessive grain but is in fact a distortion of the gelatin emulsion.

I've never had it with my own films (or a customers) and I've been processing since the mid 1960's


I am saying that there's a relationship between the slight shifts in grain size with a +/- 5ºC temperature deviations, which are inside acceptable limits, the grainy negatives with sloppy processing (a bit more deviation_ and the excessive grain that results instead of full reticulation with modern hardened films. There is a trend, and I have seen all 3.


As these are independent of the actual development itself the effective increase in graininess has to be explained another way.

I've never said that a deviation of +/- 5ºC will give excessive grain, but equally while it may quite acceptable it may well not be quite as fine as a well monitored process.

Ian
 
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lxdude

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I'm going to throw this out there.
I know reticulation to be a cracking or crazing of the emulsion from temperature shock. If an emulsion reticulated it would stand to reason that it would "wrinkle" slightly. That is, as the emulsion pulls apart slightly it has to go somewhere, so it would go "upward", away from the base. It seems that would result in the crystals occupying a smaller area, as viewed through the negative. So reticulation on a micro scale could maybe cause a "clumping" effect. Possibly the slight "wrinkles" could cause viewing through part of them to be at a slight angle, increasing the density slightly.
Just some thoughts.

I have donned my helmet and Nomex long johns as a precaution.:wink:
 

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The effect of the emulsion expanding slightly due to the absorption of water can be seen when you hang up a roll of film to dry. It usually curves with the emulsion side to the outside of the curve being slightly longer than the film base on the inside. Obviously it would also like to curve along the length of the film but it can't as it is too long (and we usually hang it up with a weight at the end to keep it straight.

I would have thought that the inevitable growth of the emulsion changing from a dry state to the swollen wet state would be far greater than any change in the already swollen emulsion by a fairly small temperature change.

Is the co-efficient of thermal expansion known for film emulsion? If so it could be compared to that of the film base to see what cumulative difference exists.


Steve.
 

Ian Grant

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I'm going to throw this out there.
I know reticulation to be a cracking or crazing of the emulsion from temperature shock. If an emulsion reticulated it would stand to reason that it would "wrinkle" slightly. That is, as the emulsion pulls apart slightly it has to go somewhere, so it would go "upward", away from the base. It seems that would result in the crystals occupying a smaller area, as viewed through the negative. So reticulation on a micro scale could maybe cause a "clumping" effect. Possibly the slight "wrinkles" could cause viewing through part of them to be at a slight angle, increasing the density slightly.
Just some thoughts.

I have donned my helmet and Nomex long johns as a precaution.:wink:


Here's the flack :D

Actually the issue is that the emulsion is swelling or shrinking, if there's a sudden temperature shock it affects the surface first it will contract with a temperature drop, expand with a rise. Modern hardening means it rarely cracks.

So something happens below the surface to the gelatin with the silver grains, causing the clumping clumping.

Ian
 

Mark Antony

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"Here's another description -“microreticulation” that LOOKS like excessive grain but is in fact a distortion of the gelatin emulsion."

Ok then explain why when you look at these 'effects' though say a microscope no disruption to the gelatin exists? After that's what we're talking about here. So if this is correct why does a tiny difference between soloution temperatures can cause massive disruption of the gelatin-indeed enough to make visual grain clumping in a print.
What you need to prove is that say a difference of ±1°c will cause the separation of the gelatin from the base.
Anything else means reticulation hasn't taken place.
I think we're going to have to agree to disagree-because I think you're entrenched in your beliefs and I need evidence of reticulation at such low levels.
 

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I have seen excessive graininess from poor processing in my student's work, but it is not the film. It is the regular type of grain accentuation one gets from printing on high contrast papers to compensate for poor exposing/processing that results in underexposed and underdeveloped negatives.

I am still willing to give the benefit of the doubt and try to cause this effect and see if I can get it under a microscope to see what may be happening.

I've already written some ideas for testing which I'll PM to you later (I'm a few time zones ahead).

Most modern films are rather robust and I have to admit that and it's just a few that appear to be problematic. Apart from excessive grain with Tmax 400 it's 20 years since I saw what I'd call grain that was more than should be expected with well exposed & processed films.

It's been very stormy and quite dark all yesterday & today, but I'll fire off some Tmax 100 tomorrow hopefully, and do my own tests as well.

Ian
 

Ian Grant

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"Here's another description -“microreticulation” that LOOKS like excessive grain but is in fact a distortion of the gelatin emulsion."

Ok then explain why when you look at these 'effects' though say a microscope no disruption to the gelatin exists? After that's what we're talking about here. So if this is correct why does a tiny difference between soloution temperatures can cause massive disruption of the gelatin-indeed enough to make visual grain clumping in a print.
What you need to prove is that say a difference of ±1°c will cause the separation of the gelatin from the base.
Anything else means reticulation hasn't taken place.
I think we're going to have to agree to disagree-because I think you're entrenched in your beliefs and I need evidence of reticulation at such low levels.

Who said gelatin separates from the base ? Only you above.

How do we know whether there's any disruption to the Gelatin ? You or I haven't looked through a microscope. It's 35 yeras since I last used an electron microscope :D

You have a hang up on what reticulation is, while the surface cracking was the old definition harden emulsions mean it's now more subtle, hence the micro description as the changes take place at a much lesser level.

Ian
 
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Ian Grant

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Ian,

Lets all have a look at that Darkroom article...
and, see if Mr. Susse provides any photographic samples for us.

Mr Susse didn't write the article.

However there was one written by Dick Dickerson, now didn't he work & write with Silvia Zakawdzki, and so it's actually a Kodak research related document :D, or like Ron (PE) something written after they left :smile:

These people say Micro reticulation exists, and they were Kodak researchers, so it's a no brainer now :D

Ian
 
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