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Thread: PCTEA anyone?

  1. #21

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    Quote Originally Posted by Photo Engineer View Post
    Keith;

    ...

    I tend to believe that it is good for quality, but without proof, I cannot say for sure. I am concerned about people mixing it up in their kitchen in a microwave to the temperature of a "cup of tea". So, I am fence sitting until I see a reason for using it that is compelling.

    As I said, I can mix up similar formulas that take no heating.

    PE
    You don't need to heat it (I didn't the first time I made some), but it makes it easier to ensure everything disolves.

    Can you explain what worries you have about warming TEA gently in a microwave (or water bath)?

    As for the fence sitting, maybe you could make make some up, then you can give us a run down on what you find. I'd certainly be interested in seeing your analysis. Remember, not everyone in this world has easy (or affordable) access to commercial developers, any many of the chemicals for other better known developers can be very hard to source.

    For me, PC-TEA is great since the ingredients are easy to get hold of, they are not especially harzardous, it is easy to mix, and it is long lasting. Last, but not least, it gives me great results.

  2. #22
    Photo Engineer's Avatar
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    TEA is an organic base and as such is toxic to humans. If a microwave is used for chemicals and food, cross contamination is possible. TEA is also flammable and is subject to ignition on a stove or in a microwave if the flash point is exceeded. There are extensive posts on this subject here on APUG and on PN. I don't care to rehash them.

    As for making it without heating, see my previous post on this. I can make equivalent or better at room temperature and use more modern technology based on my EK experience. So, you are asking me to try a 50s Chevy that might catch fire when I have a brand new BMW that will not catch fire under any circumstances.

    Now, that is an an exageration of course, but I used it to emphasize that PCTEA is a rather simplistic formula with no hard data to back up image structure or curve shape. At least, none that I have seen here!

    The bottom line is that if it works for you, use it. For me, my negatives involve a lot of work. I prefer to use one of the industry standards to insure quality results.

    PE

  3. #23

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    PE, thanks.

    I am well aware of the risks, but I don't think it useful if someone just says "it's dangerous", and doesn't qualify why. Adding the why to these threads helps to ensure that everyone is kept well informed - not everyone will search (or get their search right to return the right results) all previous threads.

    You're BMW analogy is not so great - even the new ones do, from time to time, go up in smoke!

    My images are important to me too, and I'm not going to gamble on something that might or might not work, or is inconsistent either. But, if I've tested something (to my own satisfaction), and others who I know come up with similar results, then I'm going to trust that it works.

    Maybe if we continue to use the car analogy, PC-TEA is an Ariel Atom - simple modern ingredients, with nothing extra added

    Given your extensive experience, would you be willing to do some tests with PC-TEA, so that there is some hard data?

  4. #24
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    50's? In 1952 I graduated from WVU with a BS in Aeronautical Engineering, got married, went to work for NACA, and started learning how to DO engineering. Analysis of flight test data led to research in simulation and human factors, which led to design of a planetarium star projector that we could make in-house, which led to design of a compact device for observing a pilot's lookpoint on the instrument panel, which led to study of mathematical models of The Human Operator, so that by the time I retired, my position description read "Internationally known for non-linear mathematical modelling of the human operator." We had analog computers to do our simulations. Each user had a plug board for programming the computer. The other guys used to say "You can tell which board is Gainer's because it always has something hanging on it that doesn't belong there."

    Simplistic? Yes, indeed. The simplest way you can do a task is the best way.

    Toxic? How many of the chemicals we use in good old fashioned developers are not toxic? If you worry about TEA, mix the PC in propylene glycol and add whatever alkali suits your fancy at time of use. Throw in some sulfite if you think it will improve the results. You can also mix PQ-TEA or PQ-Glycol. See if I care, is how we ended other childish arguments.
    Gadget Gainer

  5. #25
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    I'm not worried about TEA Patrick, I'm worried about HOT TEA in my microwave or on my stove! I use TEA all the time. I would like to mention that DEA is a big impurity in some samples of TEA and it is more volatile.

    I really don't care what anyone uses, as long as they are aware of any potential problems or dangers. Nothing more nor less. And, while you were chalking up all of those kudos in Aeronautical Engineering, I was getting similar ones in the field of photographic science and engineering and in chemistry. So?

    PE

  6. #26
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    I left out the photography part. If I told you about that, I'd have to kill you. At least that 's what they told me while I was photographing the bolt holes during fatigue tests of a certain medium bomber.

    I suppose this means you would not use HC-110. It doesn't stop at TEA. It goes all the way down to DEA compounds.
    Gadget Gainer

  7. #27
    Photo Engineer's Avatar
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    I use HC-110, but it goes in the darkroom at 68F not in the microwave or on the stove! I already said that though in a previous post.

    And my unclassified military work is partly on display in my gallery. I carried my very own issued pistol to do just as you say in your post if it became necessary. I also carried Geneva convention ID in case of capture and 3 or 4 types of currency in case of going down "wherever". Again I say, so?

    PE

  8. #28
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    Deep sigh... This certainly isn't where I intended this thread to go when I started it

    Sadly yours,

    Ash

  9. #29
    Photo Engineer's Avatar
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    Ash;

    I agree. I must add that at Kodak, every 6 months or so we had to take chemical safety courses, fire prevention courses and also have regular bloodwork to test us for chemical uptake by our bodies. This was all safety related and for our good!

    I am sensitive to this subject and want to earnestly promote this in the readership here on APUG so that we do not engender any potential criticism if such unsafe practices are promoted here! I'm sorry if this topic keeps coming up and keeps causing the same litany of pros and cons. Some people like to defend the opposite opinion.

    I'm sorry, but I simply oppose use of kitchen equipment for darkroom chemistry. A kitchen is no place for chemicals! If you must, get separate equipment for the darkroom that does the job, but above all, do things safely. Having been in a number of fires in the lab even when being as safe as possible, I know how the unexpected can happen even when trying to anticipate it.

    I'm sorry you feel that way, but I was trying to put forth an honest effort that I felt was my obligation as an experienced lab chemist and photographic engineer.

    PE

  10. #30
    Murray Kelly's Avatar
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    As an old LTCOL (vietnam) I say, 'uhhh?' C'mon - get it back to the thread.
    The only thing in a microwave oven that could ignite vapour is the on/off switch. Microwaves themselves are just heat waves. And very effective they are, too.
    Does anyone have personal knowledge of an unfortunate outcome of warming TEA in a microwave oven? Theory is all very well, but practical experience beats it by a mile.
    Gadget has described in a very detailed way how to avoid vapour escaping outside the mixing bowl. I have to admit it seems like overkill to me.
    Nobody in their right mind is going to drink tea/coffee that hot. I'm also a physician. Darwin rules - OK?!
    So, back to the OP.
    PCTEA (with or w/o DEA* - a red herring in the present argument in my assessment) is a very much a 'peoples' brew that challenges the old D-76/ID-11 etc. I don't mean to sound socialistic! :-) . It's the sort of stuff that frees one from the 'bought in a packet' mentality many newbies are led into believing is the 'way to go'. All the ingredients are so simple to buy - compare that w the old Kodak formulae. Gainer's original premise was - 'who needs SO3?' struck a deep chord with me.
    PE seems to me to be overly anxious about the safety of hot TEA and not the advantages/disadvantages of a homebrew HC-110 equivalent. Yes, I know, safety is important but let's not get too carried away. Anyone reading here isn't a complete safety idiot. I always extinguish my cigar when I am working w hot alcohol.

    BTW - did you have to promise that you would shoot yourself if you gave away any Kodak secrets? :-)
    Murray

    *I note that HC-110 IIRC has DEA in the MSDS. Correct? A small increase of pH over TEA.

    Quote Originally Posted by Photo Engineer View Post
    I use HC-110, but it goes in the darkroom at 68F not in the microwave or on the stove! I already said that though in a previous post.

    And my unclassified military work is partly on display in my gallery. I carried my very own issued pistol to do just as you say in your post if it became necessary. I also carried Geneva convention ID in case of capture and 3 or 4 types of currency in case of going down "wherever". Again I say, so?

    PE

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