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  1. #441

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    Quote Originally Posted by Photo Engineer View Post
    Mark; I'll bet that some would find it convenient to have the formula and the mixing instructions in one long post that they can cut and paste for their lab. Could you please do that. I know it would be nice for my own work. Thanks. PE
    Wow; it's been awhile since I posted the formula. Here it is:

    Propylene glycol ................. 16 ml
    Sodium metaborate 4 mol ..... 2.2 g
    Ascorbic acid ..................... 4.5 g
    Phenidone ......................... 0.05 g

    I find it useful to multiply this formula by 3 and store in a little 64-ml bottle sold by the Formulary. I suggest *not* using a dropper-cap because they let more oxygen in.

    Mix everything at about 75C, stirring continuously. Dissolve each ingredient before adding the next, except that Phenidone may be added when most but not all of the ascorbic acid has been dissolved. It only takes a few minutes to dissolve each ingredient. It can be hard to tell if dissolving is complete because there are many tiny bubbles that look like particles of powder. Stop stirring and if they tend to float upward, you're done.

    To use, weigh into a beaker at the rates of 22.8 g/L of concentrate and 45 g/L of sodium sulfite, and then add water. Stirring for 3.5 min at 20C will dissolve all the sulfite.

    Here are times in minutes at 20C:

    Tmax-100 13.75
    Tmax-400 12
    Tri-X 13
    Acros 13.5
    Neopan-400 16.5
    PanF+ 12.25
    FP4+ 16
    HP5+ 14
    Delta-100 13
    Delta-400 17
    Delta-3200 25

    These times might change a little as I do some re-testing.

    "D316" is a temporary name. I'm thinking of calling it "KF-1" where "KF" means "keep frozen". It stores fine in the freezer, and I'll speculate that it'll last at least two years frozen.

    I'm investigating reducing both the metaborate and ascorbic acid. This might allow us to use Dimezone S without crystallization.

    Mark

    EDIT: To put everything in one posting, I should have added the following about the results.
    Compared with XTOL, this developer:
    * Has the same grain or a hint finer.
    * Sharpens a little less.
    * Has the same density-curve, but with a slightly higher shoulder, and the toe might be slightly softer, but the difference is so small that it's hard to tell.
    Last edited by albada; 01-10-2013 at 07:12 PM. Click to view previous post history. Reason: Added image-quality results

  2. #442
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    Thanks. I'm sure everyone will enjoy this.

    PE

  3. #443

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    Quote Originally Posted by Photo Engineer View Post
    Thanks. I'm sure everyone will enjoy this. PE
    Ron or anyone else:
    If you decide to mix this, could you weigh the beaker, thermometer and stirring rod, both before starting and after finishing the mixing? The difference between those pre- and post-weights will be the total weight of concentrate you got. It will include the carry-out loss on the thermometer and rod, so it should be accurate. Divide that by whatever you multiplied the formula by (I suggest 3x), and you get the g/L of concentrate to use. It should be about 23 g/L. Whatever number you get, that's the number you should use when using the developer. I'm curious what number somebody else gets after careful measuring.

    I just checked the accuracy of the syringe I use for measuring propylene glycol (PG), and discovered that it's just over 1% short. A more accurate weight of concentrate should be more like 23.1 g/L instead of 22.8. But for normal usage, specifying "use 23 g/L of concentrate" will be plenty accurate.

    Note that the weight of raw ingredients is 23.326 g, using a sg of 1.036 for PG. With the syringe-correction, mine weighs 23.1 g. That's a loss of about 0.2 g, which should be the weight of PG and water that got steamed out. Some PG is lost through vapour, so water-loss is even less than 0.2 g. But 2.2 g of sodium metaborate 4 mol contains 0.8 g of water. That tells me little water is steamed-out. So I suspect D316 could be mixed at room-temperature, although it would take hours or perhaps days to dissolve it all. And you can forget about steaming-out water (referring to the discussion about this a few weeks ago).

    Mark

  4. #444
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    Mark, thanks for the repost of the entire formula. I'm gearing up to process some TMY this weekend.

    FWIW, I like the name D316. Makes me feel like being in on a secret.

    -- Jason
    All this has happened before, and all this will happen again.

  5. #445
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    What's a Mol? As in: Sodium metaborate 4 mol 2.2 g

    Is this a different Sodium metaborate than found at Photographers Formulary?

    You may think this a dumb question and perhaps it is, but ... I want to be sure I have the correct chemistry.

    Thanks for your efforts, they are appreciated.

  6. #446

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    @kb3lms: If I recall, you used a different amount of PG when mixing, so you'll use a different weight from the 23 g/L I mentioned above. Of course, you can measure by volume instead. The different PG also might mean that your dev-time will be a little different from mine. Let us know how it goes.

    Quote Originally Posted by Bruce Osgood View Post
    What's a Mol? As in: Sodium metaborate 4 mol 2.2 g
    Is this a different Sodium metaborate than found at Photographers Formulary?
    You may think this a dumb question and perhaps it is, but ... I want to be sure I have the correct chemistry.
    Thanks for your efforts, they are appreciated.
    Bruce, actually, you bring up an interesting question. Folks get confused because the names of sodium metaborate changed decades ago as folks got a better understanding of its structure. The old and new names don't match, causing confusion. Sodium metaborate 4 mol is also called "sodium metaborate dihydrate" because each molecule has two water molecules attached to it. Yes, the Formulary sells the correct kind, and in fact I bought mine from the Formulary.

    Mark Overton

  7. #447

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    Do you have any trouble measuring the

    Phenidone ......................... 0.05 g

    even times three that's pretty small. Where I buy my Phenidone they indcate they will not measure out less than .5

    I don't mix much from scratch....just a question.

    Thanks

  8. #448
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    Make the phenidone up at 10x in alcohol. That would be 1/2 gram say in 100 ml of alcohol. Then add 1 ml of this to the concentrate.

    And guys, always weigh out viscous liquids. Never measure by volume.

    PE

  9. #449
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    On the PG, I ended up with a slightly different amount. I don't remember why. Since I had multiplied the formula to use 0.25g phenidone (smallest I was comfortable weighing) I think it had something to do with that. Anyway I had used a slightly different amount of concentrate to make 1 liter and the pH was slightly off. We had decided that I should have used the correct amount. I also used the 8 mol variety Sodium Metaborate.

    I can report that the small bottle of concentrate is sitting on my shelf entirely unchanged from the day I mixed it. I can also report that I tried developing a few frames of homebrew emulsion (TLF2) in it and the contrast was quite low compared to D-23 or D-76 1:1. However, the contrast of that batch of emulsion was low anyway compared to other batches I had made, which are all lower contrast than commercial films.

    I like the idea about dissolving the phenidone in alcohol and measuring it out that way.

    Jason
    All this has happened before, and all this will happen again.

  10. #450
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    Quote Originally Posted by Photo Engineer View Post
    Make the phenidone up at 10x in alcohol. That would be 1/2 gram say in 100 ml of alcohol. Then add 1 ml of this to the concentrate.

    And guys, always weigh out viscous liquids. Never measure by volume.

    PE
    Anyone have accurate numbers for the weight of 6 ml of HC110 concentrate ?
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2



 

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