please allow me to answer in english. I can stumble along reading dutch but donīt make me write it :-)
In respect to Kentona it really is a matter of the base material. I believe that Harman are doing their best to solve the problem but sometimes investments necessary are just no longer justified by market turnover. Especially base paper problems. Base paper is made in huuuuuuuuuuuge quantities. Did you ever visit such a factory ? Those machines are highly efficient but often a minimum of 20 tonns of paper mash and more has to be produced and usually there is one machine for one type of paper.
As far as Polywarmtone is concerned speaking to the emulsionist is not going to bring back Polywarmtone. The Polywarmtone technology is highly complex. If you look up the hungarian patents you will find over 6 highly skilled Drīs and engineers who were involved in the setup of the technology as a whole.
Many things need to fall exactly in place: Kettle size, Kettle shape, shape of the stirrer, positioning of injection pipes, dosing pumps etc. together with the formula.
If you start transfering the formula to a differently constructed precipitation vessel different crystals with a different shape will form.
This will have effect on the tone of the images produced as well as on the detail contrast and overall brilliance which was a major advantage of the Polywarmtone paper.
Ofcourse it could be adapted but the costs involved are high. We are talking hundreds of experiments and hours after hours of expensive mantime.
Modern emulsion manufaturers are likely to use a different technology for their precipitation than Forte did. I believe Harman does too. Their technology is advanced over Fortes in respect to the loss of batches (apparently very little), batch to batch consitency and scalability of processes. Their formulations have been adapted to their technology over the years. Fortes technology produces this wonderfull paper but they drove on a different road than the larger manufacturers making Polywarmtone the peak of an outdated manufacturing-system.
I have to admit that I donīt know much about Fomas emulsification. Maybe they are somewhat comparable but I doubt it because both Foma and Ilford went to modern high speed Silverbromide-Silveriodide emulsification technologies a long time ago.
Thus my conclusion would be that neither Fomas nor Ilfords technology is likely to be adaptable to the Polywarmtone formulas in a snap.
Neither is that used by us for ADOX MCC/MCP.
To me there are two options:
1) Forgett about "the true PW" and live happily with what Foma, Ilford and we have to offer including what might be in the piepline from the respective players may it or may it not be based on Fortes formulations but different in outcome*.
2) Invest in the dismanteling, mooving overhauling and reassembly of the original precipitation equipment and make Polywarmtone again the way it used to be spending a considerable sum of money on this venture.
Number 2 was roughly calculated by us and we came to the conclusion that one needs about 2 times more turnover with Polywarmtone than Forte had in the last years to refinance it within 5 years which would be the maximum timeframe if you even want to start talking to possible investors. Forte had major quality problems with the emulsions in the end. These problems probably can be fixed because they are not immanent to the technology.
But still I think no one can be blamed for beeing more than carefull with such a decision under todays market circumstances with a continuous steady decline.
I hope this helped to clear up some rumours and I am looking foreward to your ideas and feedback
* I want to add that "different in outcome" does not have to mean it is inferior. Just different for now.
Reply to Fotoimpex
The reason Harman gave to discontinue kentona was that they couldn't replicate kentona in the Harman facility. The reason was not the availability of paper for the base. At the moment I am printing on kentona made in the Harman facility, and it is perfect. The reason Harman is giving in its statement can never be true. The problem is not kentona, the problem looks like an integrity problem. But, it might a miscommunication within Harman or elsewhere.
Mirko, your description of the difficulties in producing a Forte PW like paper are absolutely correct. I wrote this here before, although with less detail. And I would be not surprised if we should read: 'that they couln't replcate Forte PW in the Harman facility'. Thus kentona has to be replaced by a Forte PW-like production' in the Harman statement. It is like the amputation of the left leg, while it has to be the right leg. These things happen.
Do you have any technical info about the adox mcp 310-312?
I see a reference to the old agfa pdf files, but is it true that the new adox is a real replica of the old paper or is there some difference?
Mirko, thanks a lot for this clarification. It eliminates a number of paralising myths.
With my limited knowledge of emulsion production, I understand that both economically and technically it's simply impossible to exactly reproduce a paper based upon outdated technology, without endangering sound business practice. That's sad. But it's also a relief. Because it means that we have to stop wishing for what's gone, and start concentrating on getting the utmost out of the existing (and future?) papers. And beautiful papers there are...
There's work to be done.
Last edited by argentic; 03-24-2009 at 05:58 AM. Click to view previous post history.
I fully agree, we should stop wishing for a variable contrast warmtoon (chlorobromide) paper. However, I would say because of a lack of qualified people to run the difficult process.
Originally Posted by argentic
But, there are other things to consider. The variable contrast papers were almost a must in the time when photographic materials were way less reliable. Nowadays, with quality assurance procedures, the relability of the photographic materials is such that one can easily use graded paper. And, the production of such a graded paper is much simpler than the production of the variable contrast counterpart. And a graded paper, like kentona ia an example of such a graded chlorobromide paper.
Therefore, one should keep the graded version and do not spent any money on the development of the variable contrast version, unless one really has the qualified people, familiar with such a production.
Last edited by argentic; 03-25-2009 at 03:50 AM. Click to view previous post history.
Reason: quote gerepareerd
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the paper is identical in all measurable parameters except for the base because the production of the base has ben changed at Schoellers in the meantime with the relocation of the line to Weissenborn. But if Agfa was to make the paper still today the same situation would have occured. Most people do not notice this difference and it is almost impossible to see.
We make the paper on the same equipment and with the same peeople as before.
Originally Posted by Jed Freudenthal
thatīs actually not what I ment. To run the process is not that difficult.
It is a question of mooving the equipment to a new location and then setting it up again. What I wanted to point out is that you need to match both: Formulation and original machines.
This is not impossible and can be done. It is a matter of expected turnover and profit versus costs of doing such.
As far as Fixed grade vs. Multigrade is concerned I woud always prefer to make more melts from my raw emulsion and sensitize them to be of variable contrast and coat one run instead of having to produce two or even three grades.
This increases your costs in coating and you loose a lot of emulsion with every change.
I agree, if you have the Forte equipment, personnel etc, there is no problem. It is a continuation of the Forte production of polywarmtone, a very nice product. But, I do not expect, these conditions are available at Harman.
Originally Posted by ADOX Fotoimpex
If, under these conditions, the production of polywarmtone will be revived wherever, it would be very good.
It is nice to have more kentona grades, but kentona came in one grade. With the current QA that is enough. Therefore, there are no losses. Harman made kentona on the Harman equipment, because I am printing on the 'Harman kentona'. Kentona is not removed for economic reasons, but for technical reasons that are not clear. And, if everythingfor kentona is available at Harman, it will be the best solution from an economic point of view. But, economy seems not the problem.
Last edited by Jed Freudenthal; 03-24-2009 at 10:34 AM. Click to view previous post history.
Economically this makes sense, unfortunatly...
Originally Posted by ADOX Fotoimpex
Are you sure your Kentona is manufactured by Harman? Simon R Galley has stated on another thread that updated labeling only means new labels, and doesn't indicate place of manufacture.