How does amount of silver content affect the look of film or paper?

I've heard a lot about how old films and papers had "more silver" in them, and was wondering exactly what implications this has. I'd assume that a lot of it, in the case of the few products today advertised as having more silver, is marketing hype. From looking at Jim Galli's photos, made with modern film and paper but old lenses, a lot of that glow (or at least what comes across on the monitor) is due to lenses used. Then there's the presence, or lack, of other chemicals like how Forte PWT went downhill after they took out cadmium etc... From those in the know about the chemistry, what exactly does having more silver, or a thick emulsion, affect film or paper, other than making it more expensive?

Some answers and explanations of the mythos may be found in here: (there was a url link here which no longer exists)

When I started in photography the first films I used were Silver rich, thick emulsions. Yes they were more forgiving of poor exposure and they needed to be most camera's / photographers didn't have light meters, but they weren't as sharp or as fine grained as modern films.

When it comes to papers I used the old Kodak Bromide & Bromesko papers back in the early 60's and the differences between papers then (and much earlier) and now is more about variations in base colour, & texture also emulsion types etc rather than silver content. It can be as simple as the super-coat giving a matt or semi-matt finish. The huge difference of the "look" is the finish not the silver content.

Ian

The above by Ian is correct. Often, silver rich emulsions were an artifact of incomplete sensitization of the grains which then required more silver halide to be coated to reach a given contrast or Dmax. If you look at a cross section of developed film or paper, you see that development is greatest at the top and least at the bottom due to attenuation of light and developer diffusion effects. The heavier the coating layer is, the more pronounced this becomes and it affects sharpness.

PE

I wonder if the issues of exposure accuracy and development accuracy come into play with the myth. The physical realities of a thiner emulsion that develops to the same opacity as a thick one would seem to argue that the thin emulsion would need more precision in exposure and processing. That may account for a lot of the myth, where people admit to the occasional outstanding image with modern materials but are disappointed with the average.

Quite right, some cameras, well rather a lot actually had virtually no exposure controls and relied entirely on the very forgiving physical properties of the films. The whole Kodak empire was based on that alone !!! (in it's early days).

Ian

Jerevan said:

Some answers and explanations of the mythos may be found in here: (there was a url link here which no longer exists)

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Adding to what was discussed in last year's thread; I'm convinced from personal experience that the "silver rich" thing is a myth. I've printed many negatives from current films, and negatives made 50 years ago, on many papers; graded, multi-grade, "silver rich technology, and modern technology. The silver rich idea is pure bunk. Current materials made with modern technology produce excellent results. There's no advantage to silver rich at all.

Photo Engineer said:

The above by Ian is correct. Often, silver rich emulsions were an artifact of incomplete sensitization of the grains which then required more silver halide to be coated to reach a given contrast or Dmax. If you look at a cross section of developed film or paper, you see that development is greatest at the top and least at the bottom due to attenuation of light and developer diffusion effects. The heavier the coating layer is, the more pronounced this becomes and it affects sharpness.
PE

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PE, very nice to have access to someone who really knows what he is talking about. Thank you.

That said, you've mentioned a few things, like sharpness, dmax etc. I am more concerned with midtone separation. I print from large negs, 4x5 and 8x10, using a drum scanner (Aztek Premier, top of the line) and wide format printers. I have two, one is dedicated to b&w. I start with Cone inks, but reformulate them to my own target opacities. I have a great RIP, which allows me to control the curve of the paper exactly (and very smoothly). Back in the 70's I was a platinum printer and my images look more like platinum prints than anything else. I am very happy with the printing, they exceed what I did in platinum.

My negs, from the 70's and 80's print themselves. Yes, using the scanner, etc. The richness is wonderful, delicious, very 3-dimensional. My experiments with modern film have fallen short. I've done a lot of testing, every film and just about every developer, some I've come up with myself.

To try and explain this - I know that any film can reproduce a 21 step tablet, no problem. But what if this was had a 2100 step tablet? Let's imagine, for purposes of discussion only - as I have no idea how many steps great film can actually separate - that the older film (Tri-X, FP4 not plus) separated all 2100 steps. This would be evidenced by the scanner able to get a different numerical value for each step. What appears with modern film is that for example, steps 1522, 1523 and 1524 will return the same value. Tones in the print appear the same across values which really ought to separate out. Filters can help but that's a sledgehammer technique.... and has other consequences. (I'm not a big fan of dark skies.)

One could also suggest an 88 key piano where adjacent keys might be hitting the same string.

I have no worries about base, no worries about dmax... the midtones are not separating. I take this to be about the lack of silver, but maybe it isn't. Maybe its just the thin emulsion.

Do you know what this is caused by? Is there a way to address it? Am I nuts?

Thanks,

Lenny

EigerStudios.com
Scanning and Printing

Perhaps there's something wrong with your techniques, or you've changed them over the years. My Tmax negs fron the early 80's are no different to the last Tmax negs I made (and they probably are the last) two months ago.

Likewise my FP3 (60's) and early FP4 negs are no different to the FP4 negs I made last November (Idon't usually use FP4 preferring Delta 100).

Ian

Well, actually I have coated film and paper in a range of from about 50 mg per square foot all the way up to about 1000 mg per square foot and looked at the curves of a single emulsion. Basically, what I stated before more or less holds true thusly:

For paper, the contrast increases monotonically as a function of silver and you can get varying contrast grades just by increasing silver. The Dmax stays constant at about 2.0 with about 100 mg of silver, and goes down on one side and stays constant as you go up. The shoulder however, sharpens as you increase silver and thus you lose shadow detail in this type of high contrast sharp shoulder paper. The ideal is to have a high dmax, high enough contrast but a soft shoulder.

For film, the same takes place but Dmax continues to go up instead of being trucated at 2.0 as it is in paper. So, you can theoretically end up with densities of over 6.0, but the contrast is so high that the latitude is low. To counter this, you must blend emulsions of different speeds and mix them in the right proportions.

If the speed separations are not right, or the proportions are not right, you get what Lenny sees. There will be a bump in the curve where the two curves overlap and this will yield two or more close densities as being the same when in fact, they are different. I've made this error myself in blended coatings where I was blending 9 emulsions to make the 3 layers of Kodacolor Gold 400, and when the bumps don't match, you get horrific crossover at each point and so you get 6 points of crossover in the negative. Of course, this was a small lab experiment and I can't claim every coating was perfect, but it illustrated the point to me.

So Lenny, when you see 2 steps or more that are the same in the mid tone area, the film has been formulated improperly or the development conditions (time-developer-agitation-temp etc) were not optimal for the film. Remember that Kodak uses one release developer for B&W films, and they cannot test for every development condition possible. So they might have a film that passes the release test but fails your test in another condition.

PE

Thanks, Ron - at least I am not crazy...

Lenny

Photo Engineer said:

Remember that Kodak uses one release developer for B&W films, and they cannot test for every development condition possible. So they might have a film that passes the release test but fails your test in another condition.

PE

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So in order to get the least crossover from the various layers of the film, that is the smoothest response curve, one would use the release developer, yes? And how would we find out what the release developer was? Say, for TMY-2? D-76?

When Kodak tests it's own developers, D-76 and XTOL, etc., one would think that they wouldn't release the developer unless it worked well with Kodak's films. By working well I'm thinking a smooth response curve with little crossover distortion. Is that not true? I can understand that the various developers will have different properties, like development time with a given film, acutance, graininess, grain structure, etc., and would perhaps not be able to give you the exact same contrast index, etc. But I expect that all Kodak developers should work quite well with all Kodak films, or I expect that Kodak will say not to use developer X with film Y.

So... are my assumptions wrong, again? This is just something I never thought to test for. I'm not even sure I know how to test for it.

As far as I can tell, the items advertised as having a high silver content are actually much cheaper, which is what first attracted me to them. I was also interested in the fact that they are relatively old formulas, or so it is claimed. I certainly love old photography, so I wanted to try some.

After using, I also noticed that they have a unique look to my eye. Whether this has anything to do with silver content I highly doubt. I think a lot of this interesting look comes from the color response and the emulsion (very delicate...must be radically different in some way...perhaps just *crummier*) rather than the silver content (which means I could probably get comparable results by filtering a more modern film).

I don't know if "better" is the right term for it, but I do like it for what it is. I am a big fan of Efke (AKA Adox) films and Emaks papers, and largely because they are so interesting looking for such a good price.

I'm not gonna sit there counting silver, but I am going to pay attention to printed results. I like what I get from these films and newer ones, so I use both.

If I understand PE, the high silver content comes from the fact that thick emulsions (due to multiple coatings) are required with the older formulations in order to get enough density and contrast. So the fact that they are high in silver is not really of design, but of necessity.

Bruce Watson said:

So in order to get the least crossover from the various layers of the film, that is the smoothest response curve, one would use the release developer, yes? And how would we find out what the release developer was? Say, for TMY-2? D-76?

When Kodak tests it's own developers, D-76 and XTOL, etc., one would think that they wouldn't release the developer unless it worked well with Kodak's films. By working well I'm thinking a smooth response curve with little crossover distortion. Is that not true? I can understand that the various developers will have different properties, like development time with a given film, acutance, graininess, grain structure, etc., and would perhaps not be able to give you the exact same contrast index, etc. But I expect that all Kodak developers should work quite well with all Kodak films, or I expect that Kodak will say not to use developer X with film Y.

So... are my assumptions wrong, again? This is just something I never thought to test for. I'm not even sure I know how to test for it.

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Bruce, doesn't Kodak have a TMax developer? My research leads me to believe that the TGrained developers all contain some glycin, and its possible that they don't work well without it. (Unconfirmed, here.) It's also possible that they just need to be developed out much further than my original testing took me. maybe they are made for people that like to print very contrasty (to my taste).

I use Efke 25, that's the one I have gotten the best results from, and I went back to D-23. I think if I understood it all better than I do, I could make the modern films work as well, altho" I would probably have better luck with FP4 Plus than with TGrained films. Most of the folks (not all) I talk to - that want old style results - hate them. (Opinion and subjective stuff here, not intended to be a statement of fact.)

Lenny

Lenny, Tmax films work incredibly well with Rodinal and Pyrocat, no glycin in either :-D

Oh and Xtol has no Gycine either . . . . .

Ian

lenny said:

I know that any film can reproduce a 21 step tablet, no problem. But what if this was had a 2100 step tablet?

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The issue is a bit like Dots/Inch (DPI) Vs Pixels/Inch (PPI) of a digital printer. The number that is interesting is Dots/Pixel (DPP). If DPI = PPI then there is one dot/pixel and the number of tones is 1. If there are 100 DPP then there are 100 linear tones (linear tones don't really count, though, but for illustration...).

So, the question of micro-contrast really revolves around resolution. If you are willing to have low resolution then you can have lots of tones.

For the largest number of tones at the highest resolution you need the finest grain film. However, there is a caveat, that if the grain size of the film is uniform then the contrast is high and although you have a terrific number of tones, they are all in a _very_ narrow subject luminance range.

Large format negatives get around the problem by having a lot of grain size variation - allowed by having a relatively large maximum grain size - and at the same time have a large number of grains defining the tone of each unit area of the final print.

Technical Pan seemed to get it's 'large-format' look from having very fine grain with a large variation in grain size. Microfilms have the same small grain size but the grain size is uniform.

Bruce;

When I last looked at the tests, Kodak used D-76 for film and Dektol 1:2 for paper (or maybe 1:3 - I've forgotten the dilution for this one). However, all Kodak films and papers have to pass some sort of quality criteria with all developers or they have an "NR" for Not Recommended" in the developer charts published, and there are a few cases of this. The bottom line is that Kodak knows how their emulsions respond to their developers and therefore are in a good position to recommend conditions and give good results. They even test with other manufacturers products. I know we used to make sure that other's products worked well with ours.

As for high silver content in old films, these emulsions were essentially dump and stir SRAD (Single Run Ammonia Digest) and had speeds in the range of ISO 3 - 200. They were coated with high silver to get good speed and contrast, but had a bowed curve shape that arched upwards in the center of the scale. They also had a soft toe and a long drawn out shoulder. This gave the printed image a distinct appearance that some liked, but that was really a distortion of the scene. Today's films have a rather sharp toe by comparison, and are almost ruler straight in the mid scales (if done properly and without 2 or 3 bumps) and a shoulder that is "way out there" to give lots of latitude. This gives the most faithful reproduction of the scene when printed, but some people dislike the way it looks.

The older films were not very sharp and not very fined grained. My ISO 40 emulsion is about 1 micron, but todays 1 micron emulsion will get you closer to 100 or 200 with better sharpness. Today's coatings are also much harder and resist abrasion during processing. They have better reciprocity and better latent image keeping. Thus, a modern film is rather hard to solarize in-camera and can be left in your glove compartment on a hot day without too much damage. All in all, things have improved in many hidden regards that you may not be aware of.

These changes began in the 70s and are still continuing. Some companies are beginning to use some of the Kodak, Fuji and Ilford modern methods as the patents expire.

PE

Ian Grant said:

Lenny, Tmax films work incredibly well with Rodinal and Pyrocat, no glycin in either :-D
Oh and Xtol has no Gycine either . . . . .
Ian

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Ian,
It certainly appears to me from your web site that you are getting some very good results. It's the web, hard to tell, of course. I'm sorry you don't live around the corner, I'd like to look at one of those negs... and discuss how you got there.

Perhaps you can answer this (if you have a densitometer) - what is your target top end density? Are you shooting for a #2 paper?

TIA
Lenny

Nicholas Lindan said:

...............

So, the question of micro-contrast really revolves around resolution. If you are willing to have low resolution then you can have lots of tones.

For the largest number of tones at the highest resolution you need the finest grain film. However, there is a caveat, that if the grain size of the film is uniform then the contrast is high and although you have a terrific number of tones, they are all in a _very_ narrow subject luminance range.

Large format negatives get around the problem by having a lot of grain size variation - allowed by having a relatively large maximum grain size - and at the same time have a large number of grains defining the tone of each unit area of the final print.

Technical Pan seemed to get it's 'large-format' look from having very fine grain with a large variation in grain size. Microfilms have the same small grain size but the grain size is uniform.

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Ummm, No. Pretty much wrong. Sorry. For example, you can have a monodisperse emulsion with low contrast! In fact, that led to the high silver content films in the first place. The undersensitized monodisperse emulsion was too low in contrast unless coated at high silver.

See my posts on micro-macro contrast and sharpness elsewhere.

PE

"They were coated with high silver to get good speed and contrast, but had a bowed curve shape that arched upwards in the center of the scale. They also had a soft toe and a long drawn out shoulder. This gave the printed image a distinct appearance that some liked, but that was really a distortion of the scene. Today's films have a rather sharp toe by comparison, and are almost ruler straight in the mid scales (if done properly and without 2 or 3 bumps) and a shoulder that is "way out there" to give lots of latitude. This gives the most faithful reproduction of the scene when printed, but some people dislike the way it looks."

Indeed. I could not agree more with this paragraph's description of films, and why they look the way they do.

In the quest for technical perfection ("the most faithful reproduction of the scene when printed"), many films have inadvertently become aesthetically unpleasing for many purposes to some people.

I think every film is great for its own thing, no matter how perfect or imperfect. I just wish there was more variety in general. It would be nice if certain manufacturers could understand that to the "fine artist", technical perfection is not the be all and end all. I see today's selection of films as very practical, very high quality, and quite usable for most things by most people, but lacking in the areas of quirkiness, uniqueness, and variety. It would not kill manufacturers to use the money made on one product to cover the losses on another, just to show their dedication to photographers in all their various forms. It's kind of like Crayola designing the best crayons ever, in a technical sense, but discontinuing 80% of their colors in order to afford it.

The sad part is that it all comes down to spending patterns. Consumers determine what products stay and what go in the end. Joe six pack determines what artistic tools I have at my disposal.

I do not hate digital. I just wish that Kodak had immediately made a boatload of money off of it, so they had some extra to throw this stickinthemud a bone by keeping the low-demand items around. I am not talking new TMax. It is too late for what I want. Once a film has been discontinued for good, it is not coming back due to the expense.

The only thing to do is enjoy it while it lasts!

Kodak (AFAIK) does not use glycin in any B&W developer. They use HQ, Metol, Phenidone, Dimzone and Dimezone-S along with Ascorbic Acid in their developers.

PE

I have used some of the Adox high silver content paper,IMO it has a distinctive look, perhaps because of the traditional manufacturing process.The look comes with the silver,even if the silver does not cause it.The Adox paper can be had from Freestyle,Retrophotographic and Fotoimpex.

Alan Johnson said:

I have used some of the Adox high silver content paper,IMO it has a distinctive look, perhaps because of the traditional manufacturing process.The look comes with the silver,even if the silver does not cause it.The Adox paper can be had from Freestyle,Retrophotographic and Fotoimpex.

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Alan;

How do you know that the paper contains high silver? An ad? If so, high relative to what?

In any event, if it does have high silver and if it is not done just right, then it will surely have a distinctive look. It will generally have blocked shadows due to the sharp shoulder.

I would have to draw a curve to illustrate this. I just may sometime.

PE

Nicholas Lindan said:

For the largest number of tones at the highest resolution you need the finest grain film. However, there is a caveat, that if the grain size of the film is uniform then the contrast is high and although you have a terrific number of tones, they are all in a _very_ narrow subject luminance range.

Large format negatives get around the problem by having a lot of grain size variation - allowed by having a relatively large maximum grain size - and at the same time have a large number of grains defining the tone of each unit area of the final print.
Microfilms have the same small grain size but the grain size is uniform.

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Nicholas, thank you, this is one of the most interesting (or potentially elucidating) posts I have read on this subject. I've read it six times to see if I can get it into my brain.... you're saying that its the uniform size of the grain that causes this effect. That's why us old timers generally don't like TGrained film.

Further, while Efke 25 is a good film for scanning because the grains are tight - it is not going to be as varied in grain size as the old Tri-X. That would make correlate to what I am seeing... It's the only film I have tried which has the quality but it's still just halfway there.

PE has also stated, if I can paraphrase here, that the change is related to the difference between a short and long toe and the long drawn out shoulder, which is not accurate, but some of us like it. I guess I am one of those. We all have our understanding of what the world looks like in black and white. It looks to me what I grew up with, which is traditional film. I wish someone would make some! Let me repeat that - I wish someone would make some!!!!!! (Someone that could do it well.)

Maybe its both of these things, or one is a means to the other...

Lenny

Lenny;

Look again. I disagree in large part with the post by Nicholas. See my comments above along with some examples that do not agree with the satements that he made. You can have a film made of all one grain size and still have a low contrast image!

I also stated that these two characteristices (toe and shoulder) were coupled with an upward bow in the negative curve. This, I will add here, caused a corresponding downward bow in the charateristic curve of the print distorting the final image in the mid tones.

PE