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  1. #11
    Ian Grant's Avatar
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    I'd ask a question back, in many previous threads you've indicated that you hadn't come across the Photocolor Chrome 6 kits at Rochester. Kodak's Harrow Research labs would have tested them.

    Yet Pip Pippard the originator was held in very high regard by Ilford & Kodak research chemists because of his innovative colour chemistry because he overcame problems they were struggling with. It wasn't remotely like the Unicolor and other US stuff that was quite poor.

    So please stop running down products you know ZERO about.

    The downside was partially costs as the 3 step process doesn't scale up, it works fine for small scale - re-use each bath 3 times then sling. But the Blix isn't easy to replenish reliably.

    Kodak & Fuji wanted to essentially just repackage their mainstream products with minimal re-formulation.

    There are very few independent companies who made/make B&W or Colour chemistry that I'd recommend Photocolor (previously Johnsons) is one and Tetenal is another. I'm sure there's a few others I've not tried who are equally as good, but then they often have Directors who are ex Major companies (often Kodak). And you know we have mutual contacts at one NY State company

    You'll notice that Paterson isn't one of them although they later merged with Photocolor.

    Ian


    Quote Originally Posted by Photo Engineer View Post
    I say use what works for you (or what appears to work in this case).

    I ask a question though....

    Don't you think that Fuji, Kodak and Agfa would have come out with a blix for films if it were possible in a reliable fashion? It would be a big selling point, eliminating one step and a few extra bottles. But, they have not. There must be some reason, right? Well, there you are. I know the reasons and I know how to get around them. All I can do is suggest that you see the patent on this subject. I've referred to it and given the # so many times I should remember it, but I do not. That gives as much explanation as is usual in a patent.

    PE

  2. #12
    Photo Engineer's Avatar
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    Ian;

    I am not clueless about R&D into blix processes up to the present date. Kodak had an active blix and bleach-fix project underway the entire time I was at EK and it was nearly 100% in Rochester. Out of this project, they came up with the new persulfate bleach and the quinone bleach which is an updated, safer version of the old quinone bleach. They also came up with Bleach III for C-41 which uses NTA for greater activity and lower pollution and the RA Fix for C-41.

    The point being that throughout this development, not one Blix for film emerged that would pass our tests for quality assurance, scalability and capacity except one! That was the one that we worked on and published in the patent. Kodak declined to introduce it because it was too late for the C41 introduction in 1970 and has been reluctant ever since for reasons that are not clear to any of us.

    In any event, your revered Mr. Pippard says here:

    http://www.photomemorabilia.co.uk/Jo...ARPippard.html

    Quote:

    "In a NEBRO (Neville Brown & Co Ltd) catalogue dated April 1954 there is illustrated a booklet (see left) written by A.R.Pippard B.Sc. entitled "How to Use and Process Ferraniacolor 35mm and Roll Film". It was available free on application. In the same catalogue, 35mm 20exposure Ferraniacolor cassettes cost 15s/3d (76p), 35mm refills cost 11s/10d (59p) and F20 (120) roll films cost 12s/3d (61p). Other roll film sizes were also available.

    Ferraniacolor home processing was based upon the Johnsons Processing Kit, which was divided into 2 parts, Part 1 - contained the first developer and colour developer - cost 5s (25p) and Part 2 - contained the hardener, bleach and fixer - also cost 5s.

    Nebro claimed (at the time) "Ferraniacolor is the only subtractive, integral tripack type of reversal film available with home processsing kits". The speed was officially 25° Scheiner (around 25ASA), though the advise in the bookssslets shown here (left & below, left) was to use 12ASA in all but the brightest of continental sunlight."
    END QUOTE

    Which is incorrect when in fact, E1 Ektachrome was in full use in 1950 here in the USA. When it was available in the UK or Europe, IDK, but the quote shows that he and his company were apparently as clueless as you claim that I am. Or maybe just guilty of a tad of hype?

    Actually, Mr. Pippard went completely under our radar and we never heard of him until you mentioned him some time back. I have no idea what his blixes did, and the reason is that if they worked well, you can be sure that they would have made headline news at the Rochester and Harrow labs. I do know that every C-41 and E6 kit on the market was tested by the EK labs. I personally tested some of them. His did NOT make the cut AFAIK.

    PE

  3. #13

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    Quote Originally Posted by Photo Engineer View Post

    I do know that every C-41 and E6 kit on the market was tested by the EK labs. I personally tested some of them. His did NOT make the cut AFAIK.

    PE
    When you are referring to kits are you referring to small volumes less than say 5 liters or all chemistry produced by other manufacturing firms that EK tested?

    If it is all chemistry how did CPAC/Trebla fair in the EK testing? Am I safe in using Trebla chemicals for C-41, E6 & RA4 or should I use EK until they are no longer viable/unavailable for me to use?

    Trebla seems to copy EK in the number of solutions and mixing instructions and told me to use the EK Z manuals if I had any trouble.
    Darkroom Equipment : 2X Beseler 23C Color Enlargers, Jobo ATL-1, Jobo CPE-2 Plus and Kreonite ProMate 16" Roller Transport Processor

    Quote Originally Posted by Greg Davis View Post
    I could shoot digital and email the image to a lab and get a digital C-print. But I want to shoot and print in my darkroom. I was born in the wrong century.

  4. #14
    Photo Engineer's Avatar
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    Trebla is part of CPAC located near Rochester. It is run by ex-Kodak engineers and they produce excellent products.

    PE

  5. #15
    Ian Grant's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    Ian;]

    QUOTE

    Nebro claimed (at the time) "Ferraniacolor is the only subtractive, integral tripack type of reversal film available with home processsing kits". The speed was officially 25° Scheiner (around 25ASA), though the advise in the bookssslets shown here (left & below, left) was to use 12ASA in all but the brightest of continental sunlight."
    END QUOTE

    Actually, Mr. Pippard went completely under our radar and we never heard of him until you mentioned him some time back. I have no idea what his blixes did, and the reason is that if they worked well, you can be sure that they would have made headline news at the Rochester and Harrow labs. I do know that every C-41 and E6 kit on the market was tested by the EK labs. I personally tested some of them. His did NOT make the cut AFAIK.

    PE
    That quote comes from the Importers of Frerrania and you've miss read it anyway. It's saying only that it was the only film available of that type with a home processing kit. It's also meaning in the UK market.

    Johnson's was a far older company than Kodak, but it appears the shareholders/owners let it run down, and when Phototechnology emerged as a separate company they went on to uickly win awards for Exports of their colour chemistry.

    They or Pippard most definitely weren't under the radar of Kodak UK, or Ilford, Fuji etc, and they made headline news in all the UK photographic press, amateur, professional & trade, as well as TV and National newspapers when they won awards. It's just you personally didn't come across them.

    We are actually arguing at cross purposes, at some point in the late 60's and very early 70's before Pippard designed the Photocolor Blix Kodak, Ilford and Agfa had all designed Bleach-fixers that overcame the previous drawbacks of Blix with high silver content films. G.I.P. Levenson and A.Green wrote papers in the Journal of Photographic Science and Ilford & Agfa filed Patents.

    Many problems with Blix were caused by a build up of carry over from the Colour Developer. This is a major reason why a blix might work well with films on a small scale such as the Photocolor kits but be far less practical for film processing in a top-up or bleed process

    Ian
    Last edited by Ian Grant; 10-03-2009 at 04:04 AM. Click to view previous post history. Reason: clarify then add

  6. #16
    Photo Engineer's Avatar
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    Ian;

    Just as you studied Developers, I and a group of associates studied Blixes, Bleaches and Fixes. I have a huge box full of patents from the US, England and Germany covering this subject along with a few English translations of Japanese patents. I even had samples of many of them, and AAMOF, still have a few here in my lab in their original packages.

    Even with a Bleach, Developer carryover can be a problem, and Kodak recommends that if it takes place a 1% - 2% Stop be used in the process. This is no problem. I have never seen patents or articles by Pippard, but have read many by Mason, Levenson and others. In fact, BP 991.412 was a seminal patent that covered a number of approaches to Blxing, but the author missed the main point of why his Blix worked and therefore the claims missed the main point of utility.

    There are acidic Blix/Stop baths that are very very active and can be made to Blix film, but they are essentially one-shot due to the fact that the high oxidation powers and acid environment kills the hypo. There are many possible Blix formulas, but only one or two that really work and work well.

    So yes, we all did discover how to make Blixes, but they will not work well with high silver/high iodide/DIR-DIAR films. Simply read the patent. I was involved in that work and did talk with these guys for nearly 30 years. I've run or been involved in running many Blix and Bleach-Fix processes during that time, testing many films, and I produced what is now the RA-4 Blix and my boss produced the Flexicolor (C-41 Bleach and Fix) Bleach-Fix system. Kodak, Fuji and Agfa all chose this route for a variety of reasons.

    I have a non-scalable version here in my lab running just fine! It will Blix film with any level of the restrainers or silver levels. But that is after an ongoing study of years. And, I have to say that Pippard passed under my radar, yes, but that includes a rather large team of people as well. I was not alone in not having heard of him, but I did know of Mason and Levenson as well as quite a few at Agfa. I knew some of these people personally BTW.

    PE

  7. #17
    Photo Engineer's Avatar
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    Ian;

    As an afterthought, I think it useful to add here that Pippard probably never heard of me either until the patent issued on film Blixing. IDK. That is irrelevant. What is important is the fact that when another company had something "better" or "more capable" than a Kodak product, everyone knew about it who had something to do with that particular product.

    That is why I, and others tested so many products. We reported on these and they were either "good" or "bad". There was a LOT of hype out there that just was not realized when tested in the lab.

    PE

  8. #18

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    I just wish I knew where I could buy liquid C41 chemicals with a separate bleach and fix step for a reasonable price.

  9. #19
    Photo Engineer's Avatar
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    Tim;

    I have the same wish, but EDTA and NTA complexes with Iron are expensive. And, Ferricyanides are pollutants.

    So, the best I can do is offer that an untried Ferricyanide bleach be used. You see, couplers and dyes are no longer tested for image stability in the presence of Ferricyanide at EK and therfore I cannot say how well the film will hold up to the stronger bleaches the Ferricyanide offers.

    So, we have a choice of an unknown that is fairly inexpensive but a pollutant and an expensive known.

    You do have a very good point though!

    PE

  10. #20
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    So is it safe to conclude that the Unicolor C41 powdered 3 bath kits from Freestyle should be avoided?
    http://www.freestylephoto.biz/10123-...er?cat_id=1001

    I just started color work here on a low volume and am somewhat dismayed and confused at the choices. I've read quite a bit but mostly from the internet.

    It seems if you try to assemble all the correct chemicals in liquid form, the places that will ship them don't have all the necessary ingredients.

    Is the Tetenal powdered kits better than the Unicolor?
    I'm contemplating trying E6 after I get a handle on the C41 process.

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