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  1. #281

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    Here is a developer that uses TEA as the chief alkali. pH of the concentrate is 10.4 and of the dilute developer 9.5.

    Distilled water (50°C) 500 ml
    Potassium sulfite (anhy) 225 g
    Hydroquinone 40.0 g
    Phenidone 5.0 g
    Triethanolamine 400 ml
    Potassium bromide 15.0 g
    Disodium EDTA 25.0 g
    Distilled water to make 1.0 l

    This formula is said to produce negatives that are very close to those of Agfa Studional (Rodinal Special). Use dilutions and times as specified for Studional.
    Last edited by Gerald C Koch; 01-13-2012 at 02:04 PM. Click to view previous post history.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

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  2. #282

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    Quote Originally Posted by Rudeofus View Post
    I use a 6x7 format camera and enlarge Delta 3200 to 10x15, 13x18 and 18x24, what do I care about grain? Sure, using 135 format with its faster lenses would gain me 2 stops, but I really like the 6x7 view finder for night shots.
    Rudeofus: You're doing night shots? And shooting into the sun? Sounds like you want to push, and have lower contrast to tame highlights. Here's a formula which does both. It's a lower priority for me, but I stumbled across it half by accident (as usual), and it might be something you'd like to tweak for your goals. If you expose and develop for midtones, it'll push the shadows for you. Unfortunately, fog is higher (with TMY-2 anyway).


    Propylene glycol ............. 25 ml
    Sodium metaborate ......... 1.2 g (1.05g is needed to convert the ascorbic)
    Ascorbic acid ................. 2.8 g
    Phenidone ..................... 0.15 g
    Propylene glycol to ......... 30 ml final volume

    Dilute 1+32 with water containing 35 g/L of sodium sulfite. Target pH is 8.2. Try 8 minutes at 20C.
    You can probably get by with 25 ml or maybe even 20 ml final volume of concentrate, but 30 ml is what I used on my first and only try. I'm guessing that the lower contrast (and shadow-pushing) is due to poor buffering causing compensation.

    Edit: I just ran the numbers through, and propylene glycol volumes of 16 ml (initial volume) and 20 ml (final volume) should work fine. This would yield a 1+49 dilution.

    Mark Overton
    Last edited by albada; 01-13-2012 at 03:56 PM. Click to view previous post history.

  3. #283
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    Quote Originally Posted by albada View Post
    Rudeofus: You're doing night shots? And shooting into the sun?
    Here are my pet projects:
    • Shoot image with silhouette trees (birds, leafs optional) with dramatic clouds and sun in the back ground. Let Tri-X display its beautiful grain structure in the clouds but turn the sun into something more than just a bright patch in the sky, see first attachment (Rollei 35S, Tri-X @ 800, HC-110).
    • Shoot moon in partially cloudy sky, try to record clouds and moon with detail, see second attachment (RZ67, Delta 400, Ilfosol 3). I could not see one bit of detail recoded in the moon, although it was only 100 times as bright as the bright edges of the clouds.
    • Shoot obscene macro with stacked lenses, suddenly Delta 3200 is a slow film in broad daylight, see third attachment (RZ67, Delta 3200, Ilfosol 3). A dev giving me extra shadow detail would be helpful, grain be damned.
    • Shoot working men in their work place, which is frequently poorly lit and obviously doesn't allow for strobes. The image in the fourth attachment (RZ67, Delta 3200 @ 6400, HC110) was ok, but not everywhere you find as much light, especially at the location where the welders work at night.


    Before the usual barrage of "use this dev" and "the contrast is too high" starts: prints 1 and 2 are heavily dodged&burnt at different gradations, so what you see is what there is in the neg. If I can find something which puts real detail around the sun and inside the moon I'd happily take it.

    Xtol and DD-X give me one extra stop compared to my HC-110. If I find something which gives me a 2-3 stops of extra shadow detail at the expense of a lot of extra grain, I'd happily take it. Before anyone says you can't get 2-3 extra stops of shadow detail: Gerald Koch means you can, the detail must be somewhere in the film already.

    Quote Originally Posted by albada View Post
    Unfortunately, fog is higher (with TMY-2 anyway).
    Have you tried adding anti foggants to your recipe? Ron has recommended KBr and benzotriazole before and at least KBr is easy to get.

    Quote Originally Posted by albada View Post
    Sodium metaborate ......... 1.2 g (1.05g is needed to convert the ascorbic)
    I have gotten everything from that recipe except for Sodium metaborate. I did get Borax and NaOH and have the strong feeling I can use these two instead but I'm not sure. Can someone confirm this or show me another way how to make metaborate from Borax?
    Attached Thumbnails Attached Thumbnails IntoTheSun.jpg   IntoTheMoon.jpg   TinyWorld.jpg   MenAtWork.jpg  
    Trying to be the best of whatever I am, even if what I am is no good.

  4. #284
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    Quote Originally Posted by Rudeofus View Post
    I have gotten everything from that recipe except for Sodium metaborate. I did get Borax and NaOH and have the strong feeling I can use these two instead but I'm not sure. Can someone confirm this or show me another way how to make metaborate from Borax?
    I had this same question a while back...I'm not a chemistry person so it took me several hours to figure this out but here's the way I see it....

    2NaOH + Na2B4o7(10H2O) + 5H2O <-->> 4NaBO2(4H2O)

    2 mols lye + 1 mol Borax (in water) is equivalent to 4 mols Kodalk in water

    80g lye + 381.37g Borax (in water) is equivalent to 551.42g Kodalk in water.

    Divide those last quantities in order to find reasonable amounts for your application.
    Note: Kodalk is the trade name that Kodak used to use for Sodium metaborate.
    Last edited by BradS; 01-13-2012 at 05:24 PM. Click to view previous post history. Reason: typos

  5. #285

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    Quote Originally Posted by Gerald C Koch View Post
    There are examples of poorly buffered developer concentrates. For example, the catechol-caustic formulae that were once popular. D-23 and that old standby D-76 are poorly buffered.
    Do you realize that:

    1. catechol itself is acting as a mild buffering agent. Plus, catechol caustic developer is by no means a good developer in light of modern industrial chemistry.

    2. D-23 is moderately buffered by sulfite

    3. D-76 original formula is actually reasonably buffered (2g/L borax for pH of 8.5-8.6ish, not a lot but not too bad for that spec.)

  6. #286
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    Thanks, Brad. Does this reaction happen automagically or does the Borax needs some help (heat, pH level, catalyst, ...) with decomposing into smaller compounds?
    Trying to be the best of whatever I am, even if what I am is no good.

  7. #287
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    Quote Originally Posted by Rudeofus View Post
    Thanks, Brad. Does this reaction happen automagically or does the Borax needs some help (heat, pH level, catalyst, ...) with decomposing into smaller compounds?
    I think it just happens when the constituents dissolve in water. Like I said, I'm not a chemistry person. I will say that using Borax and lye dissolved in water in this ratio has always worked for me.

  8. #288

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    Quote Originally Posted by Rudeofus View Post
    As I mentioned before, I don't think little Rudeofus with his admittedly highly limited knowledge of chemistry overall and photochemistry in particular will revolutionize film developers.
    What I’m saying is that experiments only give you tiny dots in the vast knowledge space. Understanding the theories allows you to interpret the tiny dots so that you can get a lot more meaning out of it, while minimizing the risk of putting yourself in pitfalls. That is learning.

    Quote Originally Posted by Rudeofus View Post
    • We don't have to beat XTOL. 99.99% of all users may judge Rudeofus-01 as complete disaster because it lasts 1 hour, develops few films[...]
    Well, this response is not necessarily directed at you, but in general, look at the title of this thread and also count how many times things are claimed to be “better” or “improved” or whatever, from XTOL or DS-10. Some postings of the present thread sound different from what you said, you know...

  9. #289

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    Quote Originally Posted by albada View Post
    Ryuji says that solvent-effect is not proportional to dev-time, but I'll at least try a new concentrate that cuts the (separately added) sulfite in half and doubles dev-time and see what it looks like. It seems that when I try something, I often get a "surprise".

    Ryuji: A few posts ago, you said that using TEA as the sole carrier in a concentrate is a poor idea. Yet PC-TEA uses this approach. What specific problems occur with doing that? If it's not feasible for a specific reason I'm interested in, then I'll drop that pursuit.
    Second point first: triethanolamine is very viscous and it is not easy to meter accurately without wasting a lot of stuff. It also solidifies easily at the low end of typical winter storage temperatures. Then, as you saw, triethanolamine is a free base and you need to add a balancing amount of acid to make a useful buffering system, as TEA’s buffering capability is essentially limited to 7.4 to 8.2 range. But then the extra TEA and acid used for this purpose is not serving a useful function other than bulking up your stock solutioon.

    Now sulfite. With DS-10, you can probably get away with 40g/L sulfite with little change in granularity, speed or tone curve. Between 10 and 40g/L the result will be film dependent. It’s probably the same with XTOL. If you use too little sulfite in these developers, one of the first thing to measure is loss of speed.

    You need to understand that, D-23, D-76, XTOL are originally intended for replenished use in deep tank processing. 80 to 100g/L of sulfite is used to keep the developer stable in these applications (of course, in case of XTOL, this failed and later dropped). It is also important to realize that, XTOL was initially offered with dilution up to 1+3 for some films, and it would’ve needed some sulfite even in the diluted working solution.

    Actually, the notion of “silver halide solvent effect” is overly inflated in some books written for darkroom enthusiasts and online forums, especially in the context of fine grain effects.

    I once had a jug of replenished developer, which was a variation of DS-10, in my darkroom. It worked very nicely and it was practical, with very minimal wastage, unlike one shot use.

  10. #290

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    Quote Originally Posted by BradS View Post
    Thanks for this. I've printed it out and stuck it to the wall of my cube. It reminds me a little of of George Box's explanation of the scientific process(*).

    (*) George Box, Stuart Hunter and William G. Hunter, Statistics for Experimenters, Wiley & Sons, 1978
    Yeah thanks for mentioning the nice classic book. Yeah it is important to identify the target/objective/goal to analyze or solve, before doing anything... otherwise things will go Iraq.....

    I should probably print up a bunch of 3x5 cards with this and put them everywhere around me.

    Ok whaaat am I doing on apug. I will log out in a few minutes.



 

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