Bob_Maxey@mtn.3com.com
Tue, 02 Mar 1999 17:50:35 -0700
>>I do believe that a careful worker rigorously testing an emulsion and
>>working out a formula and procedures can replicate an emulsion. Jim
>>Browning obviously does, and he does a good job of it. The problem as I
see
>>it lies in assuming that this "perfected" formula will work precisely the
>>same in the hands of another worker. If I follow your formula and
>>procedures, they may well work; but they may not meet my needs, and they
>>may not work well.
First of all, please read what I said. I mentioned Jim Brownings formula.
It can be done. What my post reply was talking about was the creation of
color emulsions. I specifically mentioned color emulsions, as that is what
the original post asked about, in part. Impossible for most of us - heck,
there is not a single person on this list that could create a successful
color film that is consistent from batch to batch, that reproduces colors
accurately or is the least bit sharp. Me included, and this is not a slam
against anyone. I can say the same thing about creating a jet airplane or a
computer microprocessor. Again I say, creating color emulsions is beyond
the skills of most people. The original post also asked about infrared
formulas. Equally difficult because of the strict requirements for this
type of material.
Jim Browning's formula does work in the hands of a careful worker. Mr.
Browning spelled out the procedure, and from the copy I have, it's not too
difficult. He was very through in his explanation. I suggest you read the
information - it is all basic stuff and because it is not a multi-layer
material like color materials are, it is easily reproducible.
FYI: Eastman Kodak published in 1950 or so, a dataguide explaining the
process of making simple emulsions. It was aimed at the beginner and those
who tried it - myself included, had no problems. It was a general formula
and simple as baking a cake. It was not rocket science, but it did provide
a simple emulsion that was repeatable, even though it was being made by
people without much knowledge
You quote E. J. Well, and it is true. But I doubt he was specifically
referring to the average worker. I assume that if complex emulsion creation
is something some novice wants to attempt, with no equipment, no knowledge
in what is required, no chemistry skills, etc., he is in for a tough time
of it. For the careful worker, however... it is not a difficult task to
accomplish the production of simple emulsions. I have personally seen the
development labs in Rochester where some very complex emulsions are made,
and it is costly to do, takes experience, extreme monitoring and a whole
lot of effort and smarts from a whole lot of clever people to create a new
test emulsion.
But then there are those two musicians who developed Kodachrome, so go
figure.
A basic emulsion is available from a dozen sources. I use several on Dupont
Gel coated Cronar plastic support stock, that includes an anti-halation /
anti-curl backing, using a Symmons Route Coater. The unit is designed for
this specific application and my coatings do not vary much more than a few
thousandths of an inch. Even at that, there are difficulties.
>>>>Perhaps you can kindly explain to me why the major film
>>>>manufacturers had such a difficult time replicating the procedures and
>>>>formulas for gold sensitization that they found in the purloined German
>>>>literature. They spent a whole lot of money (and a whole lot of
>>>>person-hours) working this out. Surely it should have worked first-time
>>>>every-time when they used the same formulas and procedures.
The FACT of the matter is there is a lot of mis-information here. It was
not simply a matter on recreating German formulas, it was a matter of not
having the complete record of what the German's did. You can't fault people
like Cornwall or Debute for their inability to recreate something, when
they were not working from the complete record. In fact, it was easy to do
this once the entire process was worked out. After that, others easily
worked with the process and with a great deal of success. Incidentally,
some people were very successful of improvising and filling in the missing
information. Also, there were problems with some of the translations and
different chemical names were used to describe some of the chemicals. This
is a major reason there were problems.
The Master Trainer for the Air Force's Vectograph Printing School was
someone I worked with closely. He also worked on German technology for the
War Department He discussed many of the problems in recreating anything the
Germans produced using their documents. I am well aware of some of the
problems.
You mentioned Portriga.... I have seen plenty of samples of Kodak Papers
that equal the old Agfa material. I have personally used the old Portiga
Rapid and compared it to the newer materials. Even Agfa can't stay
consistent. In looking through sample books and my own work, there was
tremendous variety in paper thickness, surface and contrast grades. perhaps
Kodak had a problem recreating Portriga./... but apparently, so did Agfa.
Many people miss the old Portriga - I do to some degree. but Eastman had no
problems delivering a material that came very close. In fact, the stuff I
have seen from Eastman is better than the old stuff from Agfa, which was
far better than the new paper carrying the same name.
I think it is not a big secret, and the problems stemmed from incomplete
information. Kodak had a talented group of chemists working for them from
the beginning, and they were well qualified to copy other materials with
very little effort. Any problems they had came from incomplete information,
not some inherent process related problem.
>>>>And of course, we won't even mention poor old George Eastman back in
the >>>>1880s
>>>>trying to figure out why his emulsions varied so much from batch to
batch
>>>>when he did the same thing every time. Why didn't it work? He
eventually
>>>>figured it out--one of those pesky variables.
Yes, let's not forget poor old George Eastman. For every account of his
'problems' there are equal number accounts of his successes. I have copies
of memos issued by Mr. Eastman and he was very proud in his company and the
ability to deliver consistent results from batch to batch. I framed a copy
of an old Kodak Trade Show Ad where George Eastman compared his papers
others such as 'Defender' and got sued. So batch consistency was a concern.
The fact is, Eastman took very little time figuring out how to achieve
success here. Plates and nitrate films did not vary as much as you seem to
believe. I have seen the results and I have printed from thousands of
plates and negatives created from the early part of the century. This was
part of my job. The last big one was printing sample prints from all Cirkit
negatives, more than 3,000 over the year we undertook this project. I know
from personal experience that there was not a big problem with consistency.
I have information in my files that bears out the fact that from early on,
he was achieving batch equality. Search the old patent literature and you
will discover that from the early days of Eastman Kodak, technology was
developed and patented that fixed these problems. I also have read work
orders, lab notes and records that were in our archives that trace the use
of virtually every paper, film, developer Kodak, Agfa, Dupont, Ansco and
others ever made and the writings tell me that there was marvelous
consistency from material to material. And I am guessing here, but from a
'Short' available materials list I compiled several years ago, it is more
than 300 different papers and films available from a variety of
manufacturers. The list is far greater.
Consistency is still a problem. I have data sheets from modern Ektachrome
that will show variations in rated speed from batch to batch - as many as 5
different exposure index numbers for the same Ektachrome.
FINALLY: Here is where I get my information. I worked for one of the oldest
Eastman Kodak dealers in the world. We were established in 1890. One
gathers a load of stuff in this period of time, and I collected a vast
quality of it. Currently, there are catalogs from more than 400
manufacturers, distributors, etc. Formulas for 1500 different commercially
available materials such as film, paper, toners, developers, fixers, etc.
More than 1000 books about photography, a garage full of unopened kits and
chemicals, samples of paper - too many to list, Packages of unopened paper
from many different vendors, Unopened film packages - including Kodachrome
Sheet Film, a complete set of Eastman Dealer Coloramas, Tons of display
materials and manufacturer literature, most every Dataguide and Book
Eastman Kodak issued from the turn of the century to when I stopped
collecting.
Much of the stuff I gathered up is not even mentioned by Kodak - even after
a complete search through the George Eastman House. I have Dealer catalogs,
sample books, letters, literature and knowledge gathered from talking with
the family that owned the company. A ton of Stuff - and I mean that more
than literally.
So, to state it again: making emulsions is Not a difficult proposition.
Making Color films is. We did not even get into compounding developers,
hardeners, bleaches and the other items a homemade color film would
require. Again, beyond all of us if consistent results are desired.
So, Rae... you wanted me to issue a rebuttal, there it is. I am not some
List Member speaking out of a hole in his you know what... I have knowledge
about many of these topics. When I speak it is from a knowledge base.
Either from hands on experience, reading my collections or talking with
people who were around when things were a bit different. I consider myself
an Expert and I can speak with plenty to back myself up.
RM
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