Some thoughts on the use and management of salts in making Silver Halides.

[Photo Engineer]

Kodak manufacturing and research drew on people from all over the world and literally dominated the patent literature on analog photography. Research was conducted in France, England, the US, Canada, and Australia during and after the war. You can weed on which did what when. The coating was done more broadly than just these countries.

Kodak had a series of aim points for speed, contrast, toe, shoulder, grain and sharpness for every product. These were used in the plant and in research. However, in some cases, these aims did differ from plant to plant for two particular reasons. Local populations preferred their photos to look different and local printing and processing equipment varied. Thus, several products were made for the European market with a slightly higher contrast (due to higher average equipment flare for example.)

To go back to the original formulas, it might be noted that the Adox formulas were also published at the end of the war and became part of the "public" knowledge base. However, Agfa engineers did help Konica set up their first major film and paper plants, and when it was disabled during the war, they helped Fuji.

After the war, except for Kodachrome work alike color films, the majority of Japanese formulas were still rather Agfa in nature until about 1960 or later.

PE

 

[Prof_Pixel]

Gee, you almost made me cry.

BTW, I get along very well with the GEH crew; don't make unjustified assumptions.

 

[Photo Engineer]

I think it worth noting that GEH has an excellent display series on the "history" of digital photography. Just for those interested.

PE

 

[MDR]

I think it worth noting that GEH has an excellent display series on the "history" of digital photography. Just for those interested.

PE

Is it called the wall of shame

Regarding patents the US-patent system is very different to the German for example patentsystem. It's much harder to file for a patent in Germany and a lot of US-Patents wouldn't get a patent outside the US because they don't conform to the minimum standards of the German patents. The very strict rules on how to file for a patent in Germany also hinder innnovation but that's another story and I have to admit that I am envious of the support US companies get from the US Government.

 

[dwross]

The histories of all these companies are fascinating. When you start trying to diagram the connections, with the mergers, the takeovers, the snatching away of top chemists from one company by another, and the industrial espionage and sabotage, it looks something like the family trees and intrigues of the royal families of Europe around the beginning of the 20th century. It would make a great multi-episode soap opera . All the "A" firms run together in my head. It's hard to get facts about Agfa and Ansco, and Adox. I'd love to hear more from Ian and MDR on these. Not to mention the firms that sprang up in eastern Europe when my back was turned. And the connection between 3M and Ferrania (??). Is there any English language publication on Fuji?

Happily, there are a few really great books on photo technology history. Just the ticket for the reading months of winter. The book "From Dry Plates to Ektachrome Film, A Story of Photographic Research", by C.E. Kenneth Mees, is excellent and easy to read. Even if I weren't a photo history geek I'd love "Memoirs of a Photochemist", by Dr. Fritz Wentzel. And, although not in the memoir genre like the other two, "Silver by the Ton, A History of Ilford Limited 1879-1979", is jam-packed with interesting history of people and technology.

 

[Photo Engineer]

It is too easy to forget that just about every country has contributed some level of advance to analog photography. The nameplates on offices at EK, as you walked down the halls, attested to this as did the names on patents.

Kodak got its share of patents in Germany. I have a few myself IIRC. As for Japanese history, it is mainly in Japanese and what I have is personal from the VP of Fuji and the VP of Konishiroku. Unless there is an English version, we may never know the details here.

As for Mees book, there was a sort of 2nd volume titled "From Ektachrome to Instant" IIRC. It makes for a lot of interesting reading.

The bottom line is that there is no bottom line, but rather just a series of different Points of View.

PE

 

[dwross]

The bottom line is that there is no bottom line, but rather just a series of different Points of View.

PE

A great subtitle for "The Book of Life"

 

[MDR]

As much as I love Kodak, Agfa, Fuji etc.. it's often the smaller companies that bought the medium forward. Wratten and Wainwright (first panchromatic emulsions), Dr. Schleussner (first film designed specifically for X-ray use and the first thin emulsion films), the Keystone Dry plate works (first Celluloid film), Lumiére (Autochrome), Perutz (first x-ray plates) and many others that are now only a small footprint in the history of the medium but without whom many advancements would not have been possible. Interesting fact both Schleussner and Agfa started out as paint and lacquer manufacturers

Our view is unfortunately very much centered on the big western names and less so on the smaller lesser known companies. And I agree with PE post pretty much every country contributed to the advancement of the photographic medium.

 

[MattKing]

Some who read over this and a few other related threads might sense a slight bit of tension therein , but that is not necessarily a bad thing.

I expect that the big entities like Kodak, Agfa et al paid a lot of attention to the more empirical adventurers like Denise. And of course, Denise relies heavily on the efforts of Kodak and others when she experiments outside the more mainstream and current processes.

It seems to me that PE and Denise have slightly different goals - their interests overlap a lot, but not in all ways.

Together they might make a really good foundation for a university faculty - just enough different to ensure exploration and rigour, but sufficiently similar to ensure a productive learning environment.

I make no comment, however, about how the department meetings might go .

I wonder what the communications were like when that product we know as Kodachrome was being first worked on by those two musicians.

 

[MDR]

Some who read over this and a few other related threads might sense a slight bit of tension therein , but that is not necessarily a bad thing.

I expect that the big entities like Kodak, Agfa et al paid a lot of attention to the more empirical adventurers like Denise. And of course, Denise relies heavily on the efforts of Kodak and others when she experiments outside the more mainstream and current processes.

It seems to me that PE and Denise have slightly different goals - their interests overlap a lot, but not in all ways.

Together they might make a really good foundation for a university faculty - just enough different to ensure exploration and rigour, but sufficiently similar to ensure a productive learning environment.

I make no comment, however, about how the department meetings might go .

I wonder what the communications were like when that product we know as Kodachrome was being first worked on by those two musicians.

+1
at least it wouldn't be boring and I would consider getting another uni degree with those two as profs

 

[dwross]

That would be a ridiculous amount of fun . The "I'd do that for free" kind of fun.

 

[Photo Engineer]

So would I.

I think that the faculty meetings would be more fun than the classes!

PE

 

[falotico]

This whole discussion has been an exciting learning experience. Where else do people battle about the best cations for halide salts? I never knew that potassium improved the quality of glass; and it never occurred to me that as the silver salts precipitated it would lead to a rise of ph in the solution. Of course horse urine is still being harvested for biological chemicals used in medicine and veterinary practice; I don't know if they collect phosphorus as a by-product. Certainly it is not an efficient method to secure the element. That happens to touch upon an area within my knowledge. But to second-guess PE about emulsions would be like telling Stradivarius how to make a violin. I hope he gets around to writing his book of color emulsions.

 

[Photo Engineer]

Well, I have to clarify one thing:

NaBr + AgNO3 -> AgBr and NaNO3. Two mildly acidic reagents give one neutral reagent and one mildly acidic one, so the pH will move slightly up (less acid by a small amount).

NH4Br + AgNO3 -> AgBr + NH4NO3 which represents a bit more acid as NH4 is a weak base compared to Na and so the pH will move slightly down. More acid by a slight amount.

And gelatin acts as a buffer so the change depends on the amount and type of gelatin as well.

Sincd NH4 ion is less effective as a complexing agent or Silver solvent as pH goes down (more acidic), its effect in the latter case will go down.

PE

 

[Polder]

Hi to you all, I´ve been away on a long vacation and am more or less startled to find a discussion like this. I am not that experienced in emulsion making, but I know quite a lot professionally about handling conflict. So if need be.... I am enjoying emulsion making not overly burdened by loads of knowledge. I can find the Information I want on the site of the Lightfarm. And I am thankful for that. But if I want to know more or something else I`ll ask it here on the forum, as I have done before or anywhere else on the Internet. That is what the internet is for, not more or less. Problem is this kind of discussions make me shy away from this most informative place. After long years of crisis Intervention and conflict nanagement now in my old age I would like to be able to read the loads of information without extra hassle. Henk

 

[Hexavalent]

...

Another thing that's now conveniently forgotten was Kodak couldn't make consistent emulsions up until the the introduction of T grain films, a technology from Kodak Ltd in Harrow.

...

Ian

Are you claiming that Kodak emulsions up until the start of T-grain emulsions (80's) was inconsistent? If so, in what way "inconsistent"? variable results? unreliable?
I know that some EK emulsions prior to that time were chosen for scientific/medical imaging for the very reason that they were so much more reliable than the other "big names".

 

[falotico]

The latest post by PE brings us back to the discussion of potassium vs. sodium, does the K+ cation form as strong a base as Na+?

 

[Ian Grant]

Are you claiming that Kodak emulsions up until the start of T-grain emulsions (80's) was inconsistent? If so, in what way "inconsistent"? variable results? unreliable?
I know that some EK emulsions prior to that time were chosen for scientific/medical imaging for the very reason that they were so much more reliable than the other "big names".

That statement of mine does need qualifying slightly but it's not wrong

First when I started photography seriously in the late 1960's Tri-X varied depending on the plant it was made in, data-sheets from Kodak for their developers would give different recommended for EI (then nominal ASA) and development times these would vary depending on whether the emulsion was made in the US, Canada or the UK. So in this case Kodak didn't have the controls they later had to produce the Tri-X e emulsion with exactly the same characteristics in different plants.

At the same time Fujichrome Professional (E4) was very consistent batch to batch in terms of speed & colour balance while Kodak Ektachrome professional films came with a recommended EI (nominal ASA) and suggested correction filtration which varied batch to batch. So in the case of Ektachrome it wasn't totally consistent batch to batch.

Ian

 

[Photo Engineer]

The Na+ and K+ ions are very much alike except for size and since the cation is not incorporated into the crystal, the size has little if any effect. Most of the effect is in ionic strength and Van der Waal's force. They are used pretty much interchangeably and based more on cost or availability. Of course there is no such thing as NaI in the strictest sense.

Ian H;

Kodak film was consistent except for the caveat I noted above about the needs of different markets. I forgot to add though that the different markets also had to adhere to different laws regarding process chemistry and effluent from the manufacturing process.

Regarding color film, Kodak tolerance was far tighter than that of any other company and as such they tried to satisfy the most exacting professional. Thus, if the film was in tolerance but off by just 0.025 in color or even less, they put in a stuffer sheet to alert the discriminating professional. Fuji and Agfa did not do this.

And, BTW, this information is in the Kodak publication "Professional Color Films" in several editions. Those interested can certainly read up on this. The film was good but to the particular professionals they tried to make it even more perfect with exact instructions.

When Fuji E6 first came out, it was so variable that Fuji was forced to withdraw it from the market until they could correct the problem. To this day, a leftover of this is the fact that Fuji suggests a different time for the First Developer of their E6 films.

PE

 

[MDR]

1. PE do you know anything about problems regarding Kodak B/W emulsions during the first Iraq War 1991. I recently met a photographer/photojournalist who moved to Ilford and Fuji from Kodak and claimed that it was because of emulsion problems and that european photographers received subpar films because of Kodak's military contracts this was not the first photojournalist I've met who told me this story. I don't really believe that it's true but after hearing it more than once I've wanted to check if there was some truth to it.

2. I honestly doubt that Agfa was any less diligent than Kodak regarding Q.C.(also a military contractor, leading manufacturer of medical films etc...) furthermore many photographers I know favoured Agfa film because it had the best color fidelity (natural colors) and consistency. Agfapan was also know for it's superior tonal (not color) reproduction especially in the midtones.

Kodak films are superb and I love using them but they weren't that superior to other manufacturers.

 

[MDR]

Regarding my previous post I just wanted to say that it is not meant to inflame or to put doubt on Kodak's high quality and Q.C. which is above reproach.

Regarding Natrium vs Potassium PE already said it they are pretty much interchangeable. Agfa and other german manufacturers prefered potassium because they were usually part of a chemical giant (IG Farben and later Bayer Leverkusen) or companies (Perutz, Dr. Schleussner) and potassium was readily available and often a byproduct of other chemical manufacturing processes. The old german name for potassium is potasche or pot ash it's history is rather bloody literally (burned animal bones) just like the old german name Potassium hexacyanoferrate is Blutlaugensalz or Bloodlyesalt (made from mostly oxblood). The old chemical names are often very interesting and tell the history of the product.

 

[Photo Engineer]

Well, German literature lists Potassium as Kalium and Iodide is spelled with a J and thus KI is KJ in German formulas. This caused quite a "discussion" here on APUG a few years ago when one person insisted that Agfa did not use Potassium Iodide simply because he thought KJ was a "secret ingredient". But yes, I mentioned that the European film industry preferred to use Potassium salts in emulsion making.

As for Keeping or quality, I don't know of any segregation of product or orders. I do know that the military used coolers or freezers for keeping film in the tropical climate of areas near the equator. Photojournalists had no such luxury AFAIK. I heard no complaints at that time, and believe me that a widespread complaint such as this would have made news in every magazine and in every newspaper in this area.

As for Agfa films, I have used a lot of them and have run comparative tests since the '60s up until rather recently (Agfa 1000 color neg), and I found them to be quite inferior to Fuji in color and raw stock keeping. I could not even keep the 1000 speed film stable in a freezer for much longer than the actual expiration date. The earlier films were much better than the later films IMHO.

PE

 

[Ian Grant]

This thread is rather skewed by the fact that some companies tailored emulsions for specific markets.

Kodachrome was far more dominant in the US than the rest of the world mainly because it could be processed relatively locally so was a practical fast option, for a fast turn-around it was useless in the rest of the world as it had to go to one of a few Kodak labs outside the US by post for processing. Towards the end Kodak tried Pro drop off points offering fast service but it was far too late.

So in the UK Kodachrome wasn't an option when a fast turnaround was needed, but Fujichrome 50D or 100D (and the E4 films before that) were. I worked alongside one of the top industrial/commercial photographers on the UK (actually I was his landlord and our darkrooms were in the same building) and I saw how consistent his Fuji results were and his frustration with Kodak Ektachrome films and that mirrored my own experiences. It was why Fuji gained such a strong position in the European market.

In the US Fuji launched an E6 film that bombed aimed at the US market we never saw it in Europe, but then Kodak made products in Europe never seen in the US. However Fuji quicly broke into a US market that had been virtually 100% Kodak's, Ansco was never a threat, and they did that on price and Quality. Kodak were so complacent they let Fuji sponsor the Olympics.

What's more important is we still have good high quality film & paper manufacturers around, it's also important that former & current employees don't use APUG as a sounding board to over-hype themselves and the companies they are or were associated with.

Ian

 

[Photo Engineer]

Kodachrome film turn around was less than a week in Asian in the '50s and '60s. In fact, Fuji and Konica made Kodachrome work alike films and ran work alike processes all over SE Asia. And they sold products as far south as AU. The problem was NOT processing, it was rather the cost of the film and the cost of the processing.

Fuji charged $10 / roll for Kodachrome processing and also $10 / roll for the film. In some countries the processing was included in the price which was higher in those cases.

The dominant films in Asia were not E4 or E3. Outside of Kodachrome or Kodachrome type films, reversal films were virtually unknown. But every store sold negative films and made prints for you in 24 hours. They also sold processing kits and the formulas were published. Fuji, Konica and Oriental all used the same (old Agfa) process and produced unmasked color negatives which used a wash after the developer to aid in bringing up interimage effects. I have many rolls of that old film in my portfolio as well as the prints to go with them.

There is no mistake, B&W films and color films were ubiquitous virtually to the present day, and virtually from every company around the world. Oriental was quite big in the far east and SEA. Far larger than we might imagine. I have a 16x20 color print of a Japanese wedding given me by the head of Oriental. It is proudly displayed in my office. It was made on their new paper made to match Ektaprint 3 and Ektacolor 30 paper.

PE

 

[MDR]

I agree the price is what killed Kodachrome and similar processes. In the last years of it's existence Kodachrome was sold in Austria for 14€ (cheap) to 22€ (more common and mega expensive) similar prices in Germany, furthermore the processing took nearly two weeks because they closed their EU processing and the film had to be send to the US. The old Agfa process was certainly not great but it was the first modern color process and the Germans and Japanese had close ties (unfortunately not for a greater good) so it's no wonder that the japanese choose to use this process. Also matching a look to a certain product had often little to do with lack of reseach but with what the costumer wanted.