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View Full Version : What's "silver rich" actually mean?


tetrisattack
03-27-2006, 11:20
I keep seeing this term bandied around but I don't really understand what it means. Most recently, on photo.net:

"...but FP-4 is more silver-rich, is smoother, with lovely gradation" compared to delta 100.

One can also see it on J&C's front page:
"Efke and ADOX films are old-school emulsions with very high silver content."

and again in their description of their polywarmtone fiber paper:
"The high silver content chlorobromide emulsion provides beautiful warm image tones..."

I understand that there was somewhat of a backlash against film manufacturers when new, manufactured grain emulsions were introduced 25 or so years ago, and I've heard the term "silver poor" used to describe t-max, along with jaded speculation that economic pressure over the rising price of silver had more to do with the new emulsions than improvements in image quality.

Now, I was probably born after the introduction of these products. I've always had the choice between tri-x and tmy. I've bought and compared fp4 to delta 100, and I like both neopan 400 and acros. My conclusion is that the newer films are usually less grainy and can produce lovely contrast.

So what's silver content got to do with it? Is pointing out the silver content of an emulsion just another way of saying that it has a vintage look? It seems psychologically in-line with labelling canned soup "HEARTY" and pasta "WHOLESOME."

Efke 25: Now with more silver! &c. :)

kaiyen
03-27-2006, 11:36
I'm interested in the answer to this, as well. I believe that there is a response curve difference with the newer films, though. Shorter toe and shoulder. Not sure if that's from the flatter grain or less silver.

allan

bmattock
03-27-2006, 11:44
I think you have it pretty close to the mark.

One can be a sticker for detail - none of these films contain any metallic silver. They contain silver halide in a gelatin suspension (incorrectly called an emulsion, lo, these many years). The developer converts some of the silver halides to metallic silver (Ag). Fixing converts the unaffected silver halides that remain (the dark areas of the photo, the light areas of the negative) to silver salts which are washed away during the washing process.

However, the process of creating the silver halide that is dispersed in the gelatin to begin with consumes metallic silver, so one can say a film is made with more or less silver.

Technically, I believe I read the argument once that the newer t-grain type film consumed MORE silver, but the halide grains were smaller and tab-shaped in a uniform pattern, so they were actually more 'silver rich' than the older style films.

However - I think you have the right of it. They are saying that a silver-rich film will have more of the 'old time' look of traditional B&W film. It will be more grainy and perhaps also have more accutance (apparent sharpness due to edge effects) in general. Although many have gone to war for the words I just uttered, that's my understanding of it.

For an example of film they way it used to look - as you said - try Efke KB 25. I believe it is now known as Adox once again (reclaiming an old name for an old - albeit different, emulsion). I am told that Begger 200 is also an 'old-timey' looking film, but have never tried it myself.

Usually, when you say a film is 'silver rich' people take that to mean it looks more or less like old-style Kodak Tri-X or Super-X, etc. Me, I'd be happy if I could get Panatomic X again.

Best Regards,

Bill Mattocks

GeneW
03-27-2006, 11:48
Perhaps silver rich film is what Rich Silfver uses :D

Gene

FrankS
03-27-2006, 11:58
In the realm of printing paper, it is true that premium papers are made with more silver (in whatever form) and produce a richer tonal gradation than non-premium papers. At least that is my understanding of it.

bmattock
03-27-2006, 12:31
"A man has nothing in this world but his honour."

And this remote control. And this lamp. And I don't need one other thing.

Best Regards,

Bill "The Jerk" Mattocks

ClayH
03-27-2006, 12:47
"Silver rich" is a marketing term like "New, improved" "Brighter, cleaner" "Low-fat" etc. It is used because people love conspiracy theories and think big bad companies love to turn out substandard products and cut corners on materials because consumers are just stupid. The term has about as much analytical rigor as proclaiming a deodorant "fresh".

But if you actually know how to do sensitometric tests on paper and film, you find the picture is a little more complicated. For instance, many of the eastern european films are touted as being "silver rich". If that is true, then how come that nasty (by implication, "silver poor" ) film Tmax 400 can build almost twice as much density as a well-known "silver rich" 400 speed film from the former Eastern bloc? In other words, even if it does happen to contain more silver per square inch than the yellow box, it is not doing anyone any good. I think it may actually reflect sloppier tolerances in their manufacturing process.

In short, it is marketing BS.

And as far as print image tone goes, that is totally determined by the size of the silver grains after development. Tiny small grains in paper give warm tones, big chunky ones are black. The size of the grains is influenced by other addtives (not silver) in the paper and the developer used.

24x30
03-27-2006, 23:13
I never heard this about films. But at papers the concentration differs between the types. For example to make a lith-print you need a paper with a higher concentration (the higher the better is the effect).

/rudi

varjag
03-28-2006, 00:00
The content of silver (and silver halide does contain perfectly good atoms of silver) in film varies, and often an order of magnitude between different emulsions. So it makes sense to talk about silver-rich and silver-poor emulsion, but one should not take them as qualifying statements. Modern low silver content emulsions are great in many respects, and there are fairly poor old-school emulsions with very high silver content.