Making Commercial Color Separation Negatives of Transparencies for the Kodak Dye Transfer Process

[DREW WILEY]

The matrix film that Bettina Haneke uses didn't come from Ekfe, and is an entirely different formulation optimized for blue laser exposure. And no, it's not available to the public. It's possible that there was a preliminary version which did come from Efke, but I'm not going to dig through my old notes. All this didn't involve investors, but a substantial university grant, unlikely to be repeated. Any serious DT revival is likely going to be reliant on some kind of philanthropic interest.

Kodak materials weren't as consistent as you imply. Towards the end, as the older technicians were being replaced by lesser experienced ones, not only was there a flawed batch of yellow dye which got out (not to mention the flip flop in its variations), but also some lesser quality receiver paper. Matrix film was being coated with especially old machinery.

I'm aware of the mottle you describe with the Efke product. It probably wouldn't bother someone looking at a larger print, but might be slightly annoying in an 8x10 contact print. I experimented with it using using both my own variation of Wash-Off relief and with the Kodak development system. But I don't pretend to be anything more than a kindergarten level DT printer still just learning the piano chords.

The swelling issue of the Efke product can be overcome. But hopefully, if there ever again is a production run of Matrix film, several issues could be redressed.

The more relevant Kodak chemists and technicians who were involved during its heyday are no longer around. But I still contend that, going forward, if possible it would make more sense to develop a product with a more cooperative toe needing less highlight masking. Much of this problem has been overcome by the special curve-restructured profiles made possible by the laser exposure route of Bettina, as well as the film-recorder re-profiling separation negs which Jim Browning employs. But for those of us who prefer a traditional darkroom route, other tricks must be used.

 

[Lachlan Young]

Kodak matrix film was very special in many ways

It really wasn't. It needed special handling because of the unhardened nature of the emulsion, but it was otherwise a very low tech product. In fact that seems to have been part of what killed it off, namely that it would have been very costly to turn it into a highly controlled, efficient and low waste (relatively) modern emulsion. You are confusing the troublesome nature of manufacturing relatively low tech (and high wastage) emulsions and the means employed to try and make them adequately consistent batch-to-batch with them having some sort of properties that you are intent on wishing into existence. They were primitive emulsions by the standards of the 1960s, never mind the 1990s.

No Kodak did not specify all characteristics Separation Negative Type I and II

It would be visible on the characteristic curve and the spectral sensitivity. Unlike what you assume, the majority market for both materials was not Dye Transfer, and the industrial colour sep market was so vast that Kodak was not the company who dictated who got the secret knowledge. Kodak were however in the business of selling lots of those films, so they sure as hell told customers exactly what it did and didn't do (and quite literally provided lengthy documents about all sorts of masking for offset & other seps that would eventually be screened). On the other hand, maybe the effects of fog on decades expired emulsions are what's distorting your understanding, a bit like how you seem to be desperately trying to get 2+2 to equal 22. Craft based colour separation processes are not particularly tricky processes up until the assembly stage. As long as the seps are correct enough, there are a lot of controls at assembly.

You also need to understand that Yule and Hunt were writing as much about optimal 4-colour reproduction for offset or rotogravure when discussing masking as they were about any other colour print process. In fact you can see (with hindsight) that both censor (or were censored) about how much they could disclose about the way that colour neg materials can utilise both masking within layers and interlayer effects (etc) to achieve near optimal colour reproduction. Getting really good colour reproduction at vast scale and speed with offset print was where the core research interest was by the time they were writing.

And if you have read Hunt properly, you will see that you are making quite a muddle out of his work, which is well explained and intended to make things clearer for the end user (such as what masks you can dispense with). There are also good (and obvious, so obvious that a glance at the data sheets will tell you) reasons why Sep Neg 1 had benefits over Super-XX, it just requires a little consideration of where Super-XX might hit the wall. There are plenty of current materials that can be co-opted.

 

[IB Photochemistry]

The matrix film that Bettina Haneke uses didn't come from Ekfe, and is an entirely different formulation optimized for blue laser exposure. And no, it's not available to the public. It's possible that there was a preliminary version which did come from Efke, but I'm not going to dig through my old notes. All this didn't involve investors, but a substantial university grant, unlikely to be repeated. Any serious DT revival is likely going to be reliant on some kind of philanthropic interest.

I spoke to Egbert and Bettina myself about this. While I can't say anything about that here, Drew doesn’t know any more than I do on this; they don't discuss technical details of their process. And what are you implying by “optimized for laser exposure”? You realize that 488 nm and 514 nm wavelengths bands of light are just parts of the a visible spectrum, which are also found in a continuous white light source as well? So its blue sensitive, and a white light source would be more than adequate to form a latent image on it as well. My source says more people than Bettina are using it with optical enlargers. Just because a material could be sensitized for a specific wavelength or have good high intensity reciprocity characteristics, doesn't make it unsuitable for white light exposure.

Kodak materials weren't as consistent as you imply. Towards the end, as the older technicians were being replaced by lesser experienced ones, not only was there a flawed batch of yellow dye which got out (not to mention the flip flop in its variations), but also some lesser quality receiver paper. Matrix film was being coated with especially old machinery.

You have no evidence of most of this. I ACTUALLY TESTED some of these alleged materials myself. Bob Pace in his Keeping Pace newsletter, mentioned the issue of the Dye Transfer paper with emulsion batch number 85803. I have a box of this (probably because people were afraid to use it) and I find it completely usable. He claimed that it was a defective batch of paper and would generate a mottle. When I tested it the densities were constant on each area of the step wedge and observed no distracting mottle pattern. Is there a bit of “imbibition grain” noise? Possibly, but it is perfectly usable paper. That “imbibition grain” appearance can occur with other situations as well most of the later production paper. Bob Pace was trying to imply that Kodak somehow lost control of the manufacturing process due to lack of master DT operators.

Yes, there was a yellow concentrate (of which I have which a bottle of) that came from Frog Prince, that did precipitate out a little over time. When it was manufactured it met their standards and would present no problems. Printers would replenish this with some older yellow dye concentrate that did not have this problem, and restore its functionality. Someone cut a corner there but it still worked when it was new, for what it was designed for.

Drew has no knowledge on how matrix film was coated at Eastman Kodak. The two individuals I spoke to, both claiming to know about Kodak matrix film manufacturing, basically said contradicting versions of the story. I won't identify these people here, except Dr. Dick Goldberg who died in 2017. It wouldn’t matter if the coating machine was “old”, it was still likely they used a very precise laminar flow of emulsion. Those tolerances can be extremely small, less than 1 micron. The overall manufacturing tolerances would need to be tighter than normal black and white pictorial films. There were more variables that would need to be tested than a simple black and white pictorial film. For example, its dye sensitometry is different than its silver sensitometry and procedures were created for technicians to measure it. Again it didn't require DT master crafts people to make good matrix film and DT materials! Its a lot of BS what Bob Pace, Tom Rankin, etc., claimed regarding Kodak's manufacturing “problems” or "defects", for their own personal selfish reasons.

 

[IB Photochemistry]

It really wasn't. It needed special handling because of the unhardened nature of the emulsion, but it was otherwise a very low tech product. In fact that seems to have been part of what killed it off, namely that it would have been very costly to turn it into a highly controlled, efficient and low waste (relatively) modern emulsion. You are confusing the troublesome nature of manufacturing relatively low tech (and high wastage) emulsions and the means employed to try and make them adequately consistent batch-to-batch with them having some sort of properties that you are intent on wishing into existence. They were primitive emulsions by the standards of the 1960s, never mind the 1990s.

I'm afraid you really don't know what you are talking about here! Kodak Matrix film 4150 was an emulsion created in the 1960's, it was not the matrix film of the 1950's. Is a dye sensitized bromo-iodide emulsion with low silver content, not “high wastage”. Since I have done some research into matrix film I can tell you that there are very special things in matrix film technology. It not a just an unhardened film with some added yellow dye. It turns out that Kodak matrix film is much more complicated than I originally thought. Master DT craft people wouldn’t normally know about this. If you think this is simple, how many kinds of tanning developers do you know about? If so, what are their reductive potentials? What is the role of Argenine in the gelatin? Some of this you wont find in the published literature.

It would be visible on the characteristic curve and the spectral sensitivity. Unlike what you assume, the majority market for both materials was not Dye Transfer, and the industrial colour sep market was so vast that Kodak was not the company who dictated who got the secret knowledge. Kodak were however in the business of selling lots of those films, so they sure as hell told customers exactly what it did and didn't do (and quite literally provided lengthy documents about all sorts of masking for offset & other seps that would eventually be screened). On the other hand, maybe the effects of fog on decades expired emulsions are what's distorting your understanding, a bit like how you seem to be desperately trying to get 2+2 to equal 22. Craft based colour separation processes are not particularly tricky processes up until the assembly stage. As long as the seps are correct enough, there are a lot of controls at assembly.

Have you seen the characteristic curve of Sep, Neg. Type I or II? Or the spectral sensitivity curves? Kodak never published it! I never said Separation films were only for DT. They have internal color isolation masking that can benefit graphic arts as well. This fact never was placed in any publication that I am aware of.

And if you have read Hunt properly, you will see that you are making quite a muddle out of his work, which is well explained and intended to make things clearer for the end user (such as what masks you can dispense with). There are also good (and obvious, so obvious that a glance at the data sheets will tell you) reasons why Sep Neg 1 had benefits over Super-XX, it just requires a little consideration of where Super-XX might hit the wall. There are plenty of current materials that can be co-opted.

I have the Hunt book myself. It covers a lot a processes and doesn't go into much detail on the use of matrices for linear color correction masks as would be required for something like DT. Looking at the correction factors for a 3x3 matrix, yes, some of the small numbers are not as significant and can be omitted without major color error. You must remember that going from a transparency to a set of imbibition dyes are two different sets. Commercial DT labs used more than two color correction masks.

Have you been able to use pictorial films to make good separations? If so, what films are you using?

 

[DREW WILEY]

"White" light might involve more scatter, although it could be narrow band filtered if necessary. Depends on what is exactly going on with that matrix emulsion. I happen to have true narrow band additive colorheads on hand, where I sometimes use the blue channel exclusively for particular reasons. In their case, it was the logistics involved, yet also challenge of keeping those blue laser exposing devices still going by hoarding up spares.

I didn't hear the consistency problems issue from Bob Pace. Well after that, and saw examples in person. Not necessarily "bad", but not "best" either.

But again, don't pretend to speak for me, or discount whom I might have spoken to myself. Lachlan already pointed out some of your inaccurate preconceptions of matrix film manufacture. And it's been cited by numerous experienced practitioners than those you just mentioned, some of whom gained access to Kodak's own formula. It has been reasonably said that matrix film was one of the simplest films to make. The bigger trick would be to make a receiver paper of equal convenience.

And it's hard to call Bob Pace "selfish" when he went out of his way to teach the craft to others. Most of his materials and even specific gadgetry are now obsolete; but he deserves a lot of credit for what he did for others in his own era.

 

[IB Photochemistry]

But again, don't pretend to speak for me, or discount whom I might have spoken to myself. Lachlan already pointed out some of your inaccurate preconceptions of matrix film manufacture. And it's been cited by numerous experienced practitioners than those you just mentioned, some of whom gained access to Kodak's own formula. It has been reasonably said that matrix film was one of the simplest films to make. The bigger trick would be to make a receiver paper of equal convenience.

You don't know what you are talking about here Drew! Lachlan did NOT point out any of my “inaccurate preconceptions of matrix film manufacture”. How much research has he done on matrix film emulsions and associated chemistry? I have found more than 300 published sources dealing with related chemistry, physics, and sensitometry of related materials. Making good matrix is not a simple task.

Assuming (in some highly unlikely scenario) some DT master printer obtained access to one of the Kodak matrix film formulations, how could they use it? There are a number of chemicals in it they don't know about (or have not means to identify based on proprietary codes), have no means to synthesize, nor would they be able to coat it on other kinds of equipment without experts in coating/material science. Manufacturing a material like matrix requires expertise in material science, physics, chemistry, engineering, process experts, and various kinds of sensitometry. It does not require a master DT craft person. So, I think if some DT operator told you they have obtained something like this they are probably bullshitting you, to make you believe in their own narrative. Even former MEC technician Frank McLaughlin (deceased) would probably not have had access to something like this. There was a lot of secrecy surrounding coating formulas.

 

[DREW WILEY]

The rebuttal to that is so conspicuous that I don't know why I even need to bother linking it. Where do you think the subsequent versions of matrix films came from - clear out of the blue? And how did several other commercial sources of dye transfer supplies, including matrix film, come into play long before that, independently of Eastman Kodak? And what makes you think Frank McLaughlin didn't pass along quite a bit? Kodak was permanently discontinuing the process anyway; they had nothing to lose. And it's also quite evident that skilled craftsmen with engineering backgrounds are perfectly capable of making their own effective smaller-scale coating machines if they have the determination to do so.

In this day and age, any chemical ingredient still extant in trace amounts can be identified and replicated by major R&D labs, or even serious University labs. It happens all the time. DT printing itself just doesn't carry enough financial incentive anymore to entice that kind of sleuthing; and any underlying patents are no doubt long expired. Dye imbibtion films came into existence well before the official era of Eastman dye transfer printing per se. The only thing stopping an even better product from emerging is lack of a market, not the technological hurdle. Kodak was basically just coasting for decades, just like "good enough" inkjet probably will once it plateaus.

Any number of Kodak products had their special tweaks. For example, their Brown Toner was especially easy to use, and could be stored for a long time in liquid form. It's no longer available; but, minus some minor preservative ingredients, a perfectly functional DIY version can be easily mixed up on demand in about ten minutes. Similarly, the allegedly secret formula for original HC-110 was dissected in a well equipped university lab, where a decade's worth personal supply was also cooked up and precisely tested for identical performance. It is still being used to develop FP4 separation negs for DT printing.

One reason legacy products continue on in unchanged form, is that once practitioners mastered certain complex skills, especially those which involved multiple-worker assembly line strategies, it would be clumsy to change, even if component products could be improved. But in this case, all the key film and paper products involved in DT printing simply aren't in production anymore. Go ahead and extol Separation Film type this and that till the end of time - all that is valid in the same sense dinosaur paleontology is - interesting, yes; but you're never going to have your own living breathing Jurassic Park. And I think Lachlan is onto something when he remarked that the alleged self-masking property you think you're seeing is just an artifact of badly outdated film.