silvergrain chemicals

Discussion in 'B&W: Film, Paper, Chemistry' started by rkmiec, Apr 23, 2007.

  1. rkmiec

    rkmiec Member

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    is anyone out there using the sivergrain products available on digital truth website.i am very interested in them due to the eco-friendly claim. a couple of questions.are they excellent products.and what are your experiences.i dont have a favorite paper yet so i am open to what papers work best with this stuff.i know that alot is open to personal preference but a good starting point would be nice.so any help would be great.
     
  2. rkmiec

    rkmiec Member

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    nobody has tried this product yet?? anyone??
     
  3. craigclu

    craigclu Subscriber

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    The group of items developed by Ryuji Suzuki are said to be off-shoots of the published formulas that are available on the net. I have tried most of the things he has worked on (but not the commercial Silvergrain versions yet). They (the homebrewed) do exactly as he states and I believe most people would be very pleased with the performance. Perhaps Ryuji can jump in on this thread and expand on the enhancements that he made on these commercial offerings? I recall mention of him synthesizing custom components that went beyond what the general tinkerer had equipment or understanding for.
     
  4. Ian Grant

    Ian Grant Subscriber

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    I can see no reasons at all to try Silvergrain chemicals.

    There are already plenty of reputable chemical manufactures with tried and tested products on the market. I've also from about 1986 spent 21 years in precious metal recovery and effluent disposal from the photographic industry.

    If everyone switched to Silvergrain products no one would notice.

    Ian
     
  5. Captain_joe6

    Captain_joe6 Member

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    So, follow up question, as I am interested as well:

    Does anybody have any practical experience with the Silvergrain chemicals? Stop, fix, and wash aid are all pretty basic things, they all accomplish the same thing and (in general) all produce the exact same effect. The developer is the big question mark for me. I want to know what its characteristics are, which should be the real test of any chemicals. How environmentally friendly something is should be secondary to how well it performs its designed task.

    But, I will admit that eco-friendly products are a nice option, for the more envornmentally concerned of us. I use whatever I can afford and make it work for me, but now that I've got a better job about to start, I'm glad to have more options, and some that I won't feel bad about washing down the drain.
     
  6. Ryuji

    Ryuji Member

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    First of all, I licensed those products to Digitaltruth but I am not engaged in sales or marketing, so what I write here should be taken as my personal opinion. You may think I'm still biased, but at the same time, I'm the user of these formulae for the longest time, so what do you expect... :smile:

    Those who are thinking about Tektol Developers can also benefit by looking up what people say about DS-14 print developer.

    Tektol Standard Developer is photographically very similar to DS-14. Improvements include higher concentration, convenience, shelf life, and some fine tuning. DS-14 and Tektol Standard Developer (TSD) pulls out the paper's natural hue and gradation, and it's also optimized for maximum effect when the print is toned. I personally prefer to use TSD and switch paper when different results are desired. If you have all the ingredients and don't mind the work to dissolve them, DS-14 is still a good option and I don't mind hearing people mixing their own at all.

    Tektol Neutral Developer (TND) is considerably more cold toned than its Standard version, and it is for people who prefer neutral to blue black hue. It also tends to boost highlight contrast slightly, so when you want crisp highlight, this works better. If your favorite developer is cold or neutral toned developer, this may be a better replacement product.

    Both TSD and TND are concentrated 10x and used in the same way as most other concentrated print developers on market. One thing about TSD/TND is that you can mix them at any ratio to fine tune the results. Say TSD is too warm but TND is too cold, you can mix 1 part TSD and 1 part TND and then dilute with 18 parts water, etc.

    Some people found TSD 1+14 (or DS-14 2+1) is a good replacement for Ansco 130 and 135. TSD or TND 1+14 is also good for chloride papers (contact printing papers).

    I personally use TSD at 1+9 dilution as my "stand-by" print developer with a range of papers. I used to mix DS-14 from raw stock but switched when Tektol came on market. I haven't found a paper that doesn't work well in it, although some paper develops slower than others. (Nor have I heard anyone saying some papers not working well in TSD 1+9.) I like the very rich black and clean white I get from AGFA MCP, Kentmere VC Select, Ilford MG4, Oriental fiber based paper, etc. I also get rich black with very nice gradation with Fortezo, Brovira and AGFA MCC. Unfortunately many of these papers are out of production.

    Current users include: fine printing pro labs, art schools, individual artists and government agencies. Based on what I hear from user feedback, users prefer these developers because of good image quality, convenience, degree of creative control and low toxicity. I always wonder how an average user can notice low toxicity (unless they believe what I say 100%) but I occasionally hear about customers (a fine art oriented pro lab) who have lab employees who get sick working in the darkroom using other products but not with mine. I think these customers are a relatively small part of all users but these are the feedback that makes me feel it was totally worth pursuing, since those people would never have mixed DS-14 from raw chemicals. A lot of improvements I put in DS-14 were not utilized in commercial and educational darkrooms until the products were offered for sale, although the formula has been up on the web for years... Now I realized that, if you have a technology that you want to see used, it has to be just as easy to access as buying a book on Amazon.com. Anything more complicated won't get used.

    Project info:
    http://wiki.silvergrain.org/wiki/index.php?title=Nontoxic_darkroom_chemicals

    Product info:
    http://digitaltruth.com/store/silvergrain.html
     
    Last edited by a moderator: Apr 25, 2007
  7. Photo Engineer

    Photo Engineer Subscriber

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    In my hands, this developer works as advertized when freshly mixed, but I must caution you that compared to Dektol 1:3, it has roughly 1/2 the open tray life or about 1/2 the capacity for equivalent volumes of solution and at equivalent activity. I used this dilution of Dektol to split the difference between Dektol dilutions and used the Tektol at suggested dilution and comparable development times to match sensitometric curves. Fresh, both developers were matched for curve shape and speed. I used Ilford MGIV paper at grade 2. Of course, if you used Dektol 1:2, the increased concentration would make the differences even larger.

    I should also add that as Dektol loses activity, you can boost it back by increasing development time, but you cannot with Tektol. Once it goes, it has gone.

    These test are simple to conduct. Just place a liter of Dektol working solution in an open tray and Tektol working solution in an open tray. Run a print through each, matching results, and continue under identical conditions to do so every day until you see a change in each. The test simulates either use or keeping as either perform the same chemical action, exhaustion, on the developers.

    I have run my tests to 240 hours (10 days) with a wide variety of developers. My standard is Dektol.

    I have not te6sted the Silvergrain fix. To date, fixes I have compounded for myself with TEA as buffer slow down the fix reaction proportional to TEA concentration, all other things being constant, but TEA does not seem to affect wash rate. I have only tested hypo content and silver content of film, I have not tested Silvergrain fix in any way, nor have I tested TEA extensively with FB support.

    PE
     
  8. Digitaltruth

    Digitaltruth Advertiser Advertiser

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    Our customers are all delighted that we have made the effort to bring these products to the market.

    Unfortunately, this forum is being used to disparage our products by people who have their own agenda. I suggest that anyone who is interested in Silvergrain chemistry read the detailed and verifiable documentation which is available on the our web site: http://www.digitaltruth.com/silvergrain/

    The negative opinions which are being expressed by one or two people in this thread are in no way supported by the facts. There are hundreds of people who use Silvergrain products on a regular basis, including high volume professional and educational customers working to very exacting standards. ALL of the feedback we have had is tremendously positive.

    We have never claimed that Silvergrain products outperform all other photo products in every aspect. Any such claim would be nonsense. Photography is a highly individual subject, and every practitioner finds materials which suit his or her purposes. Silvergrain products have certain benefits, and a large number of attributes which most darkroom workers will find extremely attractive.

    Judge the products for yourself and don't believe biased "tests" carried out with the sole intention of finding "faults". If you conduct your own tests you will find that Silvergrain products: exhibit extremely low toxicity, provide superb control through the use of two different print developers which can be mixed together or used in different dilutions to alter image tone, have excellent shelf and tray life, have very high capacity, produce the greatest possible effect in combination with sulfiding toners, offer the fastest possible wash times, are suitable for use with staining-type developers, offer a unique alkaline system which is fully compatible with acid stop bath, etc... etc...

    There is nothing wrong with sticking to tried and trusted formulas, but as a company we have teamed up with Ryuji Suzuki to provide innovative products which offer unrivalled levels of ECO-friendliness. Silvergrain chemicals easily equal or outperform many leading brands, but contain no Metol, hydroquinone, borates, EDTA, DTPA, or NTA. Silvergrain products are the safest commercially produced photo chemicals available anywhere.

    Dektol contains Metol and hydroquinone. Tektol contains neither, and of the many users who have switched from Dektol to Tektol, we have not had one single person tell us that the tray life or capacity is less. On the contrary, all of the reports we have had suggest that every person who has made this switch prefers the overall qualities of Tektol. We are currently putting together a list of testimonials and will publish this soon. I'll post a message in the Sponsor's Forum as soon as its ready so that everyone can read this genuinely independent feedback themselves.

    It really is a shame that in an era when the big companies are looking to reduce their ranges of traditional photo products, or are going out of business altogether, that some people want to knock the small businesses which are trying to keep the industry alive. On top of this, unlike many of the other photo retailers who simply rebrand old formulas, we have started manufacturing something genuinely brilliant, unique and good for people. Why would anyone want to knock that?
     
  9. PHOTOTONE

    PHOTOTONE Member

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    There may be allergy or ecological reasons to use Silvergrain chemistry, but tests don't lie, and if tray life is important, it looks like PE has proven that Dektol wins. No need to get defensive about it.
     
  10. aldevo

    aldevo Member

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    I suspect Clayton, Ilford, Champion, A&O, and whoever owns EK's chemistry unit would disagree.:smile:

    In an era when product choices are diminishing the announcement of any new product line is most welcome.

    Folks like Ryuji, PhotoEngineer, and Gainer have been very willing to pass along their knowledge to the rest of us. At the end of the day, we'd all like to think we're doing valuable work in keeping the analog photographic tradition alive - but these guys really are doing something to lend us hope that we can scratch the analog itch if our worst fears about the industry become a reality.
     
  11. Digitaltruth

    Digitaltruth Advertiser Advertiser

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    Our own tests show that Tektol has a superior tray life and shelf life to Dektol.

    Conditions and testing methodologies differ. PE seems to have left a tray of developer in the sink for 10 days and run one print a day through it. Although he may have found a way to produce a result which shows off Dektol's resistance to oxidization, that is not a real world test, and it is clearly not part of a suite of tests designed to independently evaluate Tektol.

    The majority of printers I know (myself included) fill a tray and use it for one session or one day. Most people who reuse print developers either cover the tray at night or decant the working solution into a bottle. Under any of these conditions, I would expect Tektol to outperform Dektol.

    Tektol is virtually inexhaustible. This means that if you take a tray of developer and run as many prints through it as you can, it will keep working perfectly. In fact, the tray will actually become empty through developer carry-over before you are likely to reach capacity.

    There are many different ways to test tray life and capacity. The best way though it to try it for yourself.
     
  12. Photo Engineer

    Photo Engineer Subscriber

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    John, you are probably correct in all of your statements about the environmentally friendly nature of these products compared to others on the market. I can't say without knowing the contents which I do not. The only disturbing implication in your post is the one that I have lied or misrepresented the facts about the tray life or capacity of the developer.

    I... DON'T... LIE!

    As a scientist, I cannot afford to lie. I can err, being human, but I don't lie. So, that said, I would not have made my post without evidence. Here are 4 pictures, the two top ones are Dektol 1:3 and the two bottom ones are Tektol 1:9, just partway into the test. The origninal image quality of the Dektol example can be regained by extending development time, the Tektol cannot. These all had exactly the same development time. Both developers dropped in activity during the test, but the Dektol dropped less.

    The test used 1 liter of each developer in an 8x10 tray. The test was conducted several times for different combinations of commercially available developers all of which performed more poorly than Dektol.

    As you can see, the fresh Tektol performed as specified when fresh but fell off rapidly. It dropped in pH rather quickly during the time of the test. The Dektol did not drop significantly in pH.

    PE
     

    Attached Files:

  13. dancqu

    dancqu Member

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    I take that as an endorsement. Great results with
    some little character of their own and an environmentally
    friendly nature. Phenidone is the least toxic developing
    agent and vitamine C is not at all. That activator,
    Vitamine C, accounts for the shorter in tray life
    span. Were I to use the developer a least
    practical volume would be put in tray
    then used for one session. Dan
     
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  15. Photo Engineer

    Photo Engineer Subscriber

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    Developer lifetime is a function of exhaustion and pH drop caused by development and air (CO2 and Oxygen).

    As such, I have run many many developer tests that have been verified by tests in the field. This test that I use is one we used at Kodak to 'certify' a developer, and developers using this method of initial testing have been sold for years. Why not use this test, it works and is quick and reliable. It is a good indicator of how the developer withstands actual use and keeping.

    After posting this, I saw Dan's post and feel this is good point. If you are going to use Tektol for one session and a limited number of prints, there is absolutely no problem, but if you have a lot of prints, and/or are called away from a session, then you can begin to see differences that can be compensated for with Dektol but may not be with Tektol.

    If you run sessions requring identical prints from start to finish, this is where tray life and capacity come to the fore. You will see this in large jobs or long jobs. There appears to be little safety factor when compared to Dektol.

    I stress again that fresh, it performs as advertized. This may or may not be important to you. I am putting this data on the table for those who may find it important.

    PE
     
    Last edited by a moderator: Apr 25, 2007
  16. rkmiec

    rkmiec Member

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    now you kids behave back there or i will turn this forum around right now.seriously though thanks for all the input.it is awesome that people feel so strongly about film and that there are places we can go for support.thanks guys.
     
  17. Alex Hawley

    Alex Hawley Member

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    I've been working on a bottle of both Tektol developers and wrote a paragraph about it in this thread recently. I think they produce results similar to Ansco/PF 130 and Agfa Neutol WA. Tray life is about the same as the Agfa developer and Dektol which is about a week after mixing if decanted to a bottle. Print life is maybe about 30 8x10s, which IIRC is about the same as Dektol. Tektol not as active as Neutol was so the waterbath technique for contrast control doesn't work with it. Tektol Neutral is not quite as active as the Standard version so prints require a little longer development as compared to the Standard version. Both are nice developers. I especially like using the Standard version on Polywarmtone (now discontinued :<)

    I have yet to see a developer that has the longevity of 130. That stuff just doesn't quit.

    As far as the environmental stuff is concerned, I have no opinion. Its not my field.
     
  18. Jordan.K

    Jordan.K Subscriber

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    I had no idea these more eco-friendly chemicals existed. I work in a custom black and white lab and would be interested in finding out more about them. I worry about cancer at times and what not and if these other chemicals aren't as harmful, then it could be a nice alternative. However, I don't think PE fibs, as he is an invaluable resource to the analog cause.
     
  19. Ryuji

    Ryuji Member

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    A couple of APUGers get political and often go the low road in almost every thread I post something, so I'm not surprised to hear that Ron Mowrey said he tested tray life etc., against Dektol, and made statements that aren't true. (Indeed, I didn't know he paid to buy my products...)

    Shortly after I came up with preliminary versions of DS-14 formula, which gave rise to Tektol Standard, I made a lot of different print developers and compared tray life by keeping them in an array of open beakers and testing the chemical state of the solution and running sensitometric strips periodically. DS-14 developer can be kept in open tray overnight for no or negligible sensitometric change, and takes many days before it dies completely. If you go through pure-silver archive anyone can see exactly how I tested these developers. I did another test run with Tektol Standard 1+9. Translating the test data into real life darkroom operations, the developer volume reduces noticeably due to evaporation of water before the developer dies. Most darkroom workers replace the developer way before this happens. Also in terms of processing capacity, unless you use squeegee to remove developer from the paper surface, you'll lose much of the developer volume before the developer comes anywhere near the exhaustion level. In reality, tray life of DS-14 and Tektol Standard compares to some of the better glycin developers.

    Anyone can search on pure-silver, APUG, and other sites for what the users say. Tektol or DS-14. I also hear that several photographic magazines are writing product reviews, and you'll know when they get published.
     
  20. Ryuji

    Ryuji Member

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    Thanks for your interesting review and information. Now I ask so that I can understand your findings... How did you measure the tray life? Do you have rough estimate of how many milliliters of solution and how many square centimeters of air surface? Also, what was the average testing temp?

    It is true that Tektol developers, especially Tektol neutral tends to take a bit more time to develop if you compare to Dektol stock or 1+1, but the reason why water bath technique doesn't work is primarily due to the difference in the developing agent. Hydroquinone is retained within the emulsion longer than ascorbate when the paper (or film in the case of film developer) is removed from the developer and immersed in plain water or alkaline bath. In my early days of experimenting with ascorbate, I also tried to make two-bath film develoeprs with ascorbate, but for this reason it does not work (well, I didn't know the reason at that time but now I do).

    True. I could make it to match the developing speed, but I thought it would be more important to make the neutral version (TND) really cold, solid black, and make it mixable with the standard version (TSD) so that people who want half cold developer can make it by simply mixing them.

    I also miss Forte papers. Fortezo was my best favorite warmtone paper that makes nice split toning effects and Polywarmtone was also very good.

    Again, I'm curious to know how you compared TSD with 130...
     
  21. Ryuji

    Ryuji Member

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    To be very precise, Phenidone is not much better than Metol, but chemical allergy is much less common and, since it is used in such a small quantity, its environmental load is much lighter and also is more easily treated in the waste water.

    Although no one asked me to remove Dimezone S from Silvergrain chemicals or formulae, I am actually getting ahead of current standard of safety and environmental damage to see a possibility of making practical developers free of any compound of the Phenidone family and is also free of hydroxybenzene or p-aminophenol derivatives (hydroquinone, catechol, pyrogallol, Amidol, Metol, glycin, etc.). I found this candidate compound in the course of improving some other developers and this compound is readily biodegradable. Not much to report yet, but will.

    You assumed vitamin C developers are short lived but that's not always the case. If you have the ingredients (which I think you do, from your postings from other threads) mix a batch of DS-14 and see.
     
  22. Digitaltruth

    Digitaltruth Advertiser Advertiser

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    Ron,

    In your follow up post, you state that ALL commercial developers failed to match Dektol in the one-off 10-day open tray test. Why didn't you mention this before? How did Tektol fare compared to other developers?

    As in the past, you have justified your claims by stating that the test you conducted was standard procedure at Kodak. Surely Kodak did not perform only this single extremely limited test on its developers. What other tests did Kodak conduct when assessing a developer, and how do Dektol and Tektol match up in those tests?

    Did you attempt to run any tests in which it was likely that Tektol or other Silvergrain products would show their superior qualities?
     
  23. Ryuji

    Ryuji Member

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    Somewhat off topic, but a lot of people asked me. "If you can make such products why don't Kodak, Fuji and Ilford make them?" That's a good question. I don't know.

    One thing I can tell though, they all tried. Those major companies own numerous US, European and Japanese patents on technologies they thought would be useful in eco-friendly processing chemicals. Based on my research, very few of them are actually used. Ilford, for example, holds a very broad US patent for concentrated ascorbate developers, although I don't see any of their products using it. Kodak has a number of patents attempting to improve the keeping qualities of ascorbate developers. What's the problem with them? In my test replicating some of their findings, their technologies worked better than some older ones but not good enough to make it commercially available. But those patents still have legal power of exclusionary rights to prevent me from using their findings.

    I off course worked around all patents that I was aware of, even ones I believe to be easy to nullify in court, but patents are written to make it difficult for the competitors to work around and still come up with something useful. (As a principle I try to avoid infringement for published formula, products, or something for my personal use, as I expect others do the same.) So these companies holding patents and not utilizing the technology are actually slowing down the technological progression. But you can't really blame them much. The market is shrinking and introducing any product costs a lot of money.

    Then Kodak and Ilford switched their strategy... rather than avoiding hydroquinone, they argue hydroquinone wasn't all that bad if you look at recent researches. Well, maybe hydroquinone was not as bad as it was once thought (depending on which research you look at). However, hydroquinone is listed on the regulated chemicals but vitamin c isn't. I believe they would replace hydroquinone if they had an option to replace hydroquinone with vitamin c without sacrificing the developer performance, ease of use, shelf life, etc. and without increasing the cost. Well, I don't have a technology to meet all those requirements; the manufacturing cost of Tektol is higher than equivalent PQ or MQ developers on market due to higher cost of ingredients and special mixing instructions. I don't get to decide the product's retail price, but I said to Jon that I hope people shouldn't have to pay extra to get the new technology. On top of that he is OK with me keeping the DS-14 formula posted on APUG and on my website.
     
  24. gainer

    gainer Subscriber

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    I don't know what happened to the patent regulations since I tangled with them. One cannot patent the laws of nature, only specific uses of them. One cannot patent prior art, even if that prior art is not patented. It seems from what I have seen of some current patents that one could patent "a mixture of any of several photographic reducing agents with any of several antioxidant chemicals and any of several alkiline chemicals for the purpose of " you name it. Such general patents may not stand up in court, but they serve the purpose of hindering those who are not wealthy enough to hire a patent attorney. I'm sure you know all this, Ryuji. It's just something I rant about from time to time.

    My only experience with patents was at NASA. We had patent attorneys. At the time, there was a cigarette commercial, the theme of which was "I'd rather fight than switch." We used to say our attorneys would rather switch than fight. Oh, well.
     
  25. Photo Engineer

    Photo Engineer Subscriber

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    Jon;

    First I would like to say that all commercial developers that I tested failed to equal Dektol. I have more to do in this ongoing series.

    Two other tests were used at Kodak, one of which did not apply and they were both much too expensive for me. However, they did verify the open tray test which I did use.

    Basically, in one of the tests, a 100 sheet box of 8x10 paper or thereabouts was flashed to Dmax over 30% of the area with a step wedge included on the edge. Sheets were equillibrated at room temperature for 1 day for latent image stabilization purposes, and then the sheets were processed one after another until the developer ceased to achieve a black dmax in the step wedge. Then the curves were plotted. (We used 35mm strips for film instead of 8x10 sheets for film developers.) We would often attempt to regain the original tone scale by developing longer. It works with Dektol, it did not with Tektol.

    This test gave results very close to the open tray 1 liter test which was ultimately used. The only difference, which was actually slight, was due to the halide salts seasoning the developer in one case, and not in the other. The drop in volume from the sheets being processed or evaporation was pretty similar for film and RC paper. FB paper caused a large drop in liquid level invalidating the test. The open tray test satisfied management and also the patent office.

    The other test, which does not apply, involved running 1000 ft rolls of paper in a continuous RT machine with replenishment. The paper was flashed to 30%, and had step wedges. The replenisher was formulated and reformulated to keep the step wedges constant. A formula had been derived for this iterative process. I never did this type of test, as I was not involved in formulating replenishers, only the start up tank or single use developers. It does not apply here.

    As I said earlier, Tektol performed as advertized when fresh. I tested only speed, contrast, image tone, dmax and dmin. I also measured pH. Tektol dropped in pH more rapidly than some developers, especially Dektol. As you can see in the pictures, Tektol is about a perfect match to the Dektol at 1:3 for 60" at 68F in all respects.

    PE
     
  26. Photo Engineer

    Photo Engineer Subscriber

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    With reference to some questions I've had put to me or seen posted, ie, 'why would someone use this type of test?', I've thought that I should post an answer.

    In R&D, often one does not have a lot of a new chemical or coating. Due to expense, you may often have 10 grams or less of a new developing agent or stabilzer, or 10 feet or so of a 4.5" coating. Therefore, it is necessary for the research scientists involved to develop an economical method of testing coatings or chemicals. It helps if the test can be done quickly due to R&D time scales.

    Therefore, the test described above, the open tray keeping was developed to meet the needs of the R&D community with limited supplies of chemistry and/or coatings.

    So, the test above was designed to work with a minimum amount of developer and paper, and was verified to be a reliable benchmark. The length of the test was established to determine safety factor and recovery factor (the ability to adjust development time to get back what was lost by keeping) which was always paramount in Kodak's philosophy of design for developer capacity, fixer capacity or even coating expiration date.

    This is not meant to give you license to go overboard in pushing things, but there is the reasoning behind my testing methodology.

    PE