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  1. #21
    Photo Engineer's Avatar
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    Several notes here to be considered.........

    Kodak sold small packages of all of its chemistry in pouches in the 80s and 90s. Entire kits were sold in small boxes about 5x7x1 inch to make 1L of process chemistry. This included all color and B&W products. I still have a few boxes here with incomplete ingredients. They were not very cost effective for the average individual. The same is true of the tablet chemistry.

    So, to me, everything here has been deja vu!

    PE

  2. #22

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    Back when I was in junior high school (a very long time ago), I remember that there were a number of tablet developers available. they were one shots, much like the Kodak foil packs. 1951 was about the last date for them. I can't remember exactly what they were or who made them, but I believe most were film developers and some were special purpose. I think one was from Agfa.

  3. #23

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    I did some pharmaceutical research in pharmacy school at purdue....

    Many many problems the binders you would need may change the chemical composition of what your working on... Tablet presses are expensive and need cause slot of heat when the tablet is formed... Lastly tablet presses are dangerous... When making tablets I had to stand behind bullet proof glass in case one of the dyes shot out and killed me

    I would go for pouches.... I have small plastic bags and keep d76, dektol, and tf2 ready to mix just add 500 ml of water and your ready to go

  4. #24
    Ian Grant's Avatar
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    "Tabloid" form photographic chemistry was available from the late 1800's onwards, an 1898 reference notes that acetic acid had to be omitted from the "Tabloid" form of a Uranium intensifier. Chemistry for the Ozobrome process was also manufactured in Tabloid for in the early 1900's.

    The major disadvantage of "Tabloid" chemistry appears to have been some tablets were more difficult to dissolve but a reasonably full range of chemistry was available from Burroughs Welcome under their "Tabloid" brand name by the 1930's and 40's.

    Ian

  5. #25

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    Preventing mixtures of dry chemicals from reacting is a very complex art. Pressing them into a tablet compounds the problems. The problem with the Tabloid products was that they did not keep very well.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  6. #26
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    Current powder chemistry from Kodak has all ingredients encapsulated in barrier layers to isolate the alkali and developing agents. Then the ingredients are packed under an inert dry atmosphere for further protection.

    PE

  7. #27
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    A lot of great responses, thanks everyone. It seems that maybe we don't see tablet chemistry these days for a good reason, though I still like the idea of small capsules of pre-weighed chemicals, along with what 2F/2F suggested.

    PE, so the individual powder elements have a barrier layer? That seems like an amazing production feat!
    If you are the big tree, we are the small axe

  8. #28
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    Yes, there is a patent on that somewhere.

    PE

  9. #29

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    Sorry bub but once again flaws with capsules.... Capsules aren't made to completely dissolve... If they were they would be quite quiescent (absorbing too much water from the the air)...

    This is evidenced by some capsules still being able to be seen in stool... Plus would you really want pieces of gelatin adhering to your neg??

  10. #30
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    In the 1960 era, I recall being fascinated by a product from ADOX being a syrofoam box with a bunch of brown glass bottles of something called "Adox E-10" developer. Each bottle had an aluminum cap, and contained 10ml of developer which was to be diluted with 500ml of water.

    I only ever had two of them, and found they worked wonderfully, but when I tried to get some more found that Adox was gone. (years alter I found Efke had bought the line) But I never saw the handy pack of developer again.

    I recall Ansco had a "Kit" with 16oz of each of the chemicals for Anscochrome, all in foil pouches. Never was brave enough to attempt that process.

    I do fondly recall the Tri-Chem pack. There was a companion product of 6 packets to make 4 oz each of Microdol-x. Since you could use Microdol-x 1:3 with water, each envelope in effect made 16oz of developer. enough for 1 roll of 120. (or 2 35mm if you did not mind overdoing the capacity)

    Around that time I found the little brown bottles of Agfa's famous film developer and used that for years.
    Charles MacDonald
    aa508@ncf.ca
    I still live just beyond the fringe in Stittsville

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