PDA

View Full Version : Emulsion Makers Book Club, Selection One: Photographic Emulsions



Pages : 1 [2] 3 4 5 6 7

holmburgers
12-10-2010, 01:50 PM
I'm not discouraged in making my own emulsions, but what I'm saying is that will a group of individuals ever be able to achieve the perfection of say, the slide films of Kodak/Fuji? It seems like the R&D necessary to produce something with that high of quality is unattainable today, without the market incentive and the years of work towards these excellent products.

All I'm saying is, can the patents and published information lead to such a result if an individual or smaller operation took up the task?

A 100 years from now, will they publish this information? IDK, but no one even knows how to operate the original autochrome machines, as an example. Perhaps if they had left detailed instructions for the public, we could.

Photo Engineer
12-10-2010, 02:11 PM
What I have tried to say in my posts here is that the books out there have been severely censored either by the authors or the companies that they represent. In addition, no definitive work has been published in just about 75 years that explains emulsion making. Therefore, although you can gain a sense of what is going on, you can spend a lot of time trying to make something that works well in your home lab.

If you take the basic Baker SRAD emulsion, which he calls "high speed", and make it today, it comes out with an ISO of about 6 - 12 because all gelatins sold in the western world are inactive, but if you modify the formula to use the methods of Sheppard et al, you can get ISO 40 - 80, which is what Baker probably intended. Well, the same goes for all other emulsion texts.

It is like reading a book on surgery from the 1800s. Not wrong, but clumsy and with many misinterpretations of observed effects.

I have been trying for 5 years to reduce the old emulsions to modern formulas, and to tack on modern techniques and modern formulas and organize them. If it had not been for the secrecy though, I would not have to be doing this. BUT, (and this is a big but), all of the techniques are out there in patents for all to see! Understanding is another thing, and capability to carry out the instructions is another. And thus, the modern core shell t-grain formulas are there as is the entire structure of Ektar put forth in one patent for all to see. I've posted the patent # for all to see in another post rather similar to this.

So, given the technology and the desire does not give you the ability to do top-of-the-line work, but it will help you understand, and what I am writing up will carry this much further for the average darkroom worker.

PE

wildbillbugman
12-10-2010, 02:17 PM
Holmburgers,
Having worked in R&D for several large companies, I know that a great deal of emphases is placed on Documentation. I think that, in the days of Autochtome machines,things were much looser. Therefor proprietary information was much more easily lost than it has been since,say,1960.
Bill

holmburgers
12-10-2010, 02:49 PM
Well that is reassuring, and I think that what you're doing Ron is very valuable. But isn't it true that patents don't discolose the "trade secrets"?

Anyways, I'm straying from the topic, but I just would hate to see color films not being manufactured by anyone... the technology is just too miraculous to forget about it IMO.

Photo Engineer
12-10-2010, 03:20 PM
The trade secrets involved are those related to how exactly the emulsion is made and coated. So, although the entire formula may be given, the mixing speed, mixer design, UF hookup and the rate of exchange are a number of things that are glossed over by saying "it an be repeated by one skilled in the art". This last part is what I am doing in my home darkroom, and I'm doing it from memory.

Whether the interest is there to use it is another matter. I doubt if anyone is willing, and so in the future I would say that we will have the following: A blue sensitive emulsion with an average ISO of 12, a contact print and very slow enlarging paper with a grade of 2 or thereabouts and that is it. Much more is possible. What is possible is an ortho or pan emulsion with speeds up to 400, and a VC or fixed contrast paper for contact and enlarging with current speeds. A simple color film and paper are also within the reach of the home worker. But, I see little serious interest in the more advanced possibilities, and just mild interest in the simpler options.

PE

holmburgers
12-10-2010, 03:30 PM
I don't think one can judge the future's interest in these things at this time. I don't know, but there are a lot of young people who are keenly interested in this stuff, and I'm not saying it's certain, but you never know what people might attempt in the future. Even if there's no real market or interest, it is possible for someone to almost become obsessed with these things, and maybe they'll succeed.

I'd like to think that once the "digital takeover" is complete, these old processes will seem that much more amazing to people and perhaps there will be some kind of a resurgence. Hmm, probably wishful thinking.

I guess as long as black & white panchro materials are obtainable, then color is possible. That is my main concern... I don't want to live in an age where every single color print has come from a printer and a digital file.

Photo Engineer
12-10-2010, 03:38 PM
A great many people still ride horses but do not get around in a horse drawn carriage. So, horses are still used, but not entirely the way they were used 100 years ago. The same will probably be true for film. Certain methods will survive and others will not. It is not our responsibility to choose which ones, but rather to do the best we can to provide as many choices as possible. And to do that, we need to provide as much correct and up to date information as possible. This includes updating formulas and dispelling myths.

PE

holmburgers
12-10-2010, 03:49 PM
Touché

wildbillbugman
12-10-2010, 04:27 PM
PE and Holmburgers (Where did you get that name?),
Please excuse my uncharacteristic optimism. It must be the painkillers! But,PE, I was not referring only to patents and publications. I was referring to internal records which would never be disclosed,accept if nobody cared. I am sure that a company like EK would have internal documents for every aspect of every process. They would leave nothing to the skill of any individual. The records must exist. Autochrome, on the other hand, probably did rely on the expertise of individuals. That was a different time.
As for the the degree of interest in one process or another, you may be gauging your estimates on numbers,rather than intensity on the part of a few people.
Bill

AgX
12-10-2010, 04:34 PM
But that documentation is made by people for themselves (and theirlikes). Once the few from R&D of those companies will have left, a lot of knowledge will be gone.

holmburgers
12-10-2010, 04:34 PM
Holmburgers is a portmanteau of my last name, Holmquist, and hamburgers. I picked the name in middle school and I've chosen to live with it ;)

That's what I mean... undoubtedly Kodak has complete documentation of every step in excruciating detail on how to create Kodachrome, Ektachrome, Portra 400, etc. Sure the patents are there, but the extra research to get to the finished product is proprietary.

Why can't wikileaks expose this instead of "diplomatic secrets", ooooh, like anyone cares about that! ;)

Photo Engineer
12-10-2010, 04:46 PM
I must reinforce previous comments here on this. No single person at Kodak knows the entire formula for any product. It is broken into steps with code numbers for ingredients. So, the instructions may read for one person, make emulsion K1650 and pass it on to stage 2. Stage 2 says give it finish XK56 with RL115 treatment and pass to stage 3. Stage 3 is coat K1650F 1:1:1 with K1500F and K2200F with NF633 at 20 mg / mole and NAZ at 100 mg/mole. Silver levels to be adjusted to 300 mg/ft square and gelatin at 5%, with drying condition D7 at speed 3. In the end, none of these people may know what any of this means nor what product it is for.

I have used formulas just like the above but far more complicated involving up to say 20 ingredients or steps / layer with nothing but codes and numbers.

To go further, I know that some products have more than one formula depending on conditions. The results may be identical, but the formula is different. This usually applies to emulsions though, and is caused by variations in gelatin, addenda, scale and silver.

I am trying to take some of that mystery out of this but there it is. If Kodak closed its doors, I doubt if anyone in a single lifetime could reconstruct more than a fraction of the product line, if that.

PE

Photo Engineer
12-10-2010, 04:47 PM
Touché

Actually, no sense of Touche was intended.

PE

holmburgers
12-10-2010, 04:49 PM
Actually, no sense of Touche was intended.

PE

Yeah, I'm not sure I use that word properly all the time... mommy and daddy could never afford fencing lessons!!

:cry:

wildbillbugman
12-10-2010, 05:12 PM
0.K.,
We will never know how the Pyramids of Egypt were constructed. And who needs them anyway. I understand both points. I still WILL make a panchromatic emulsion fast enough for in-camera color separation.All the Digital cameras will fry in the upcoming super solar flair. Now I will get back to reading.
God Bless Oxycodone!
Bill

Jerevan
12-10-2010, 05:18 PM
I am not trying to sidetrack the discussion even further here, but having worked in museum and archive settings I know enough to know that when a company decides to leave a product (or field of action) by the wayside, there is more luck than anything if even the smallest bits of the really interesting documentation is retained. Even if the technical documentation does survive, there is also a "silent knowledge" that almost always gets lost if there isn't a tradition of apprenticeship or similar.

Regarding the Kodak codes: it sounds like a pretty fool-proof way of keeping people in the dark. :)

Jerevan
12-10-2010, 05:38 PM
It's late around here so excuse the rambling. Something Denise touched on earlier is the practical vs the theoretical parts of emulsion making. The knowledge of the properties of bromine is good in of itself and a theoretical discussion may lead somewhere good and unknown. But the practical making, basically the re-invention of emulsion making that we need is something else. The two parts may intersect but the prime goal as is still making an emulsion, right?

Mustafa Umut Sarac
12-10-2010, 05:44 PM
PE ,

I had been attemped to order analysis of PN55 at a chemistry lab at France which work for Kodak France.
Is it possible to crack the ciphers with chemical , physical analysis ?
For example , Brovira , It is still possible to find and you can sell the formula to a factory at china.
You dont lose money but satisfaction is guaranteed !
Electricity and raw materials are 10 times cheaper there and environmental problems are not a concern.

Umut

AgX
12-10-2010, 05:45 PM
The knowledge obout the ingredients of a film doesn't tell you that much about making that film.

Jerevan
12-10-2010, 05:47 PM
No, that's what I guess I was trying to say in a few more words. :)