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  1. #1
    Photo Engineer's Avatar
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    Why use brand name process solutions with color films

    After writing about this a lot and answering off forum question, I thought a post was finally needed.

    Firstoff, B&W films are made to a release spec using a single developer, but with adjustments can be used with any developer. This does not mean that the results will be the same from developer to developer, but only that good results can be obtained with the single layer B&W coating in spite of the fact that come contain blends of 2 or 3 emulsions to get long tone scales.

    But, when it comes to color films, they contain many many layers and 9 or more emulsions that must never cross over, must influence each other in an exact way, and even though each film is different they must reproduce things in a pleasing manner. To achieve this with films having speeds from 25 - 1600 is a difficult task. To achieve this, the film is built FOR THE DEVELOPER and not the reverse which is often the case for B&W.

    Therefore, all films must funnel through one developer, and one tail end process to give an acceptable release result. This means that an 800 speed film and a 25 speed color negative film must both filter through the same narrow funnel.

    Now, if the reverse were true, I could design a developer that gave good results with a 25 speed film, but chances are the 800 speed color film would be deficient in some regard. In fact, if compared to the release specifications, both films might fail, but the 25 speed might be almost there while the 800 speed film would fall far outside release specs.

    So, those who design a "developer" fool themselves if they say they have a good developer when in fact it is acceptable and has only been tested with 1 or 2 films. It is especially deceptive if they have not compared it with the identical test with a brand developer from Kodak or Fuji.

    We used to mount 2 cameras on a bar and slave them with 2 releases that were coupled. We then shot over, under and normal sets on several films that were then processed in a "check" and an experimental developer for comparison purposes. Included in this test was RMS granularity, sharpness, and interimage / color reproduction charts.

    In most cases, the films failed in some manner when you designed the developer for the film. It just reinforced the dictum that with color, one designs the film for the developer.

    So, if you have brand X, and the producer of brand X does not make a film, then you can be assured that the developer was designed for A film. Not all films possible, but I'll warrant that it was designed and tested with a single brand of film and found satisfactory. This is good, but is it good enough for your pictures? IDK.

    I have to answer after seeing the data that the home brew developers out there are not good enough for me.

    But, you do what you want. I just wanted to give you a different perspective. One gained from years of lab work!

    PE

  2. #2
    fotch's Avatar
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    I get it. You made this very understandable. Thank you very much.

    Itís too bad that small volume users and amateurs can no longer buy the low volume kits. I cannot buy either Fuji or Kodak chemicals for my use. I donít know if Fuji ever had a smaller kit like Kodak.

    I know for reasons beyond my knowledge that Kodak probably had to discontinue the product. I have run several businesses and itís just the way it is sometimes. You would think itís to their benefit but thatís based on no facts or responsibilities so I trust they did what they must do when they dropped the smaller kit.

    From my perspective, it looks like I have two choices. Buy in large volume and discard what I cannot use. But just where do I dump this stuff? It raises my cost per roll and the money is all spent up front. Times are tough so itís not really an option for some of us.

    The other choice is try what is available (home brew, buy off brands) with the film one is going to use and see if itís acceptable. If it is, stay with that combo, if not, try another film.

    I had hope to band together with others in my area and perhaps share the quantity and cost. Never found anyone interested and itís probably more of a PITA anyway.

    Oh well, thatís how the shutter clicks.

    Again, thank you for sharing your knowledge and insight.
    Items for sale or trade at www.Camera35.com

  3. #3
    Photo Engineer's Avatar
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    Look for small companies to begin to repackage Kodak kits or kits formulated with genuine Kodak formulas in smaller quantities for C-41 and RA. I suspect this will take place.

    PE

  4. #4
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    Quote Originally Posted by Photo Engineer View Post
    Look for small companies to begin to repackage Kodak kits or kits formulated with genuine Kodak formulas in smaller quantities for C-41 and RA. I suspect this will take place.

    PE
    I haven't seen the small volume kits in a long time, when I used them, ahem nearly 30 years ago, the developer was something akin to 7 bottles of various sizes that needed to be mixed together. If this is still the case, then splitting a large quantity kit might be difficult or expensive to get it right.
    Paul Schmidt
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    The greatest advance in photography in the last 100 years is not digital, it's odourless stop bath....

  5. #5
    Photo Engineer's Avatar
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    Paul;

    For any given solution, there are a maximum of 3 bottles to prepare a working solution, so Developer is A+B+C and Blix is A+B. Bleach is 1 bottle and fix is 1 bottle. Stabilzer is 1 bottle. This pertains to RA and C-41.

    So, C-41, Developer A+B+C, Bleach, Fix, Stab/final rinse. 6 bottles. RA, Developer A+B+C, Blix A+B, 5 bottles.

    Does that bother you? It is not any different than at present.

    PE

  6. #6
    fotch's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    Look for small companies to begin to repackage Kodak kits or kits formulated with genuine Kodak formulas in smaller quantities for C-41 and RA. I suspect this will take place.

    PE
    Great, I thought of doing this myself. What about longevity? OK if sealed with Nitrogen after splitting?
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  7. #7
    Sirius Glass's Avatar
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    PE,

    Thanks.

    Steve
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  8. #8

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    fotch wrote"Great, I thought of doing this myself. What about longevity? OK if sealed with Nitrogen after splitting?"

    Works for me and many others here. I use the 10 liter Kodak RA4 kits and mix 1 or 2 liters of working solution.

  9. #9
    Ian Grant's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    Look for small companies to begin to repackage Kodak kits or kits formulated with genuine Kodak formulas in smaller quantities for C-41 and RA. I suspect this will take place.

    PE
    What's more common is for enterprising retailers to split the Minilab packs, this certainly happens with Tetenal C41 & RA-4 chemistry. This works out far cheaper than officially packaged small kits for the consumer and the retailer makes a bigger markup.

    But some other points.

    The fact that "the film is built FOR THE DEVELOPER and not the reverse" makes it very much easier to design a substitute developer that will work well with all films designed for the process.

    What do we mean by a "Brand Name process" Kodak made the formulae etc for E6 & C41 processes widely available in the 70's, this was the only way they could get consensus between manufacturers to allow the introduction of the new processes. Some labs (particularly in Europe) were running E4 and Agfa transparency lines, and separate print not particularly cost effective.

    So we had E6 & C41 films & chemistry from: Kodak. Fuji, Agfa, Sakura/Konica, Ferrania/3M

    And compatible chemistry from: Tetenal, Champion (May & Baker), Trebla etc.

    Then there were the kits from smaller companies like Photon Technology, Paterson, Unicolor, Fotospeed etc.

    All the large companies produce first rate products, properly researched and tested for cross compatibility.

    The issues with quality really arise with the smaller brands, some were very much better than others, mainly depending on th skills of the photo-chemists behind them. For instance the Paterson colour products weren't as good as Photocolor (who they later took over), and many E6 kits weren't up to standard.

    Some of the unbranded published formulae will be excellent, some were used commercially by colour labs and equally as good as anything from Kodak or Fuji. Others we can't tell without trying.

    Unfortunately most commercial colour formulae remain unpublished, but it's likely we'd see significant variations between manufacturers that in practice produce almost indistinguishable results

    Ian

  10. #10
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    Nitrogen packed split kits will work just fine AFAIK at the present time. They must be split under nitrogen as well though, in a glove box.

    If the chemistry is licensed, then it is identical between Fuji, Kodak and "whomever" but the problem is that many companies make kits that are just good enough. Those that use blixes for film, or lack a stabilzer step introduce the potential for problems down the line.

    And, designing the film for the developer is not easier otherwise we would have perfect work alike kits from anyone. That is the problem here. Some manufacturers are missing the mark, and if they are using the formulas I see published on the internet, I know why! I doubt if any small manufacturer is using HQMS in E6 work alike kits.

    PE

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