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  1. #21
    MikeS's Avatar
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    Quote Originally Posted by Adrian Twiss
    How does one get hold of a copy of the photo lab index? I understand they are quite old and out of print.
    The PLI is still available new from Morgan & Morgan. Having said that, for B&W stuff you would probably be better off looking for an older version, they're on eBay every so often.

    -Mike

  2. #22
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    Quote Originally Posted by fhovie
    I have both the darkroom cookbook and the film developers cookbook. The film developers cookbook also explains why certain chemicals do certain things and will help you understand why you would use as certain chemistry for different situations. I highly recommend it - that you read it cover to cover - It is more than a recipe book. In my darkroom, they are both -must-haves-
    I have both. I must say that I consider the Darkroom Coolbook the more useful. Both bools are full of "conventional wisdom" of which some is not universally true. A fine-grain developer may have lots of sulfite or none. A fine-grain developer may have low pH or high. It may be concentrated or dilute. High acutance developers are an enigma. You may find what you think is high acutance, and when you look closely, you see tonal distortions. It may be that is what you want. You must be careful when you mix a formula that is proclaimed to be this or that because it contains this or that or because it is diluted 1+1000 or=== you name it. Wait til you have tested it against what it is claimed to be better than.

    I have gotten noteworthy or notorious for some things, mostly for putting ascorbic acid in everything, but also for using organic solvents for stock solutions. My objective in most cases has been cheaper and/or longer lasting with quality as good as D-76. I don't use any more sulfite than is needed, not because it is a dreadful menace, but because it turns out to be the most expensive component of many developers and is not necessary for getting the qualities I want. If I can make a gallon of developer that costs less than a dollar to make and has all the qualities I need, I think that is worth passing on. Enough preaching.
    Gadget Gainer

  3. #23
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    Amen Brother! - BFWIW - Both cookbooks are very good at taking someone from magic soup to an intrinsic knowlege of the basics. It was the gateway for me that got me off all that store bought stuff and convinced me it was ok to roll my own. I still use them as fall back references and sometimes conventional knowlege is adaquate for the non-inventor types - like me. I am confident in mixing up chemistries that someone else designed and enjoy knowing what function each component has in the operation. I will likely not experiment with substitutions or changes to produce different results. There are some wonderful and brilliant folks right here that do that and share. So I can spend more time making negatives and less time pondering the magic soup. - AND MANY THANKS to all of you here that do share - it makes this type of art so much more rewarding.
    My photos are always without all that distracting color ...

  4. #24
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    Quote Originally Posted by Ronald Moravec
    I will second the Photo-Lab index.

    Mixing chemicals is not necessarily cheaper. I once figured compared Dektol and D72. They were almost the same. The advantage is you can make non commercially produced developers. Two part developers are one example. Home made D76 will get little pieces of precipitate in it after several weeks. The commercial product will not do this.

    You need a good scale to measure small amounts. This will be $100 or more. Almost anything is ok for sodium sulfite as it is non critical and does not effect activity.
    I second Peter's recommendation of the Vitamin C (ascorbic acid) developers. Cheap, non-toxic, and excellent results.

    I don't agree that you need a good scale. Get a good set of kitchen measuring spoons; in Greece, they'll likely be the metric variety rather than the teaspoon or tablespoon variety here in the U.S., but that's easily adjustable. Then look up the chart of gram/teaspoon equivalents in Henry Horenstein's "Beyond Basic Photography." I've been using the teaspoon measurements for all my chemical processes for nearly 30 years with absolutely fine results. The plain fact is, though this is horrifying to the more science-lab types, is that very little in photochemistry demands extremely fine measurement precision.

    1 teaspoon sodium carbonate
    1/2 teaspoon ascorbic acid
    4 ml. 1% Phenidone stock (1/2 teaspoon--1 g-- Phenidone dissolved in 100 ml 90% isopropyl alcohol)
    1 liter water

    For some films, e.g. Delta 400, you may want to substitute sodium metaborate for the carbonate to give reasonable developing times.

    Fine grain, excellent tonality, long scale with plenty of shadow detail. What more can one ask for?

    Larry

  5. #25

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    FYI Larry, you can use half as much carbonate for Delta 400. It's counterintuitive that you can use the same volume of carbonate and ascorbic acid, but it works. 10 mins at 74F gives a contrast range of 1.2. The grain is nice, but the accutance isn't exciting.

  6. #26

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    Measuring Spoons are *not* a replacement

    I don't recommend measuring spoons as a replacement for a scale.

    Here's why:

    When you are measuring powder the amount of mass per unit volume is referred to as the "bulk density". This entity is usually quite different than the regular notion of "density" which referes to the amount of mass per unit volume if the material is in a single piece.

    The big problem with "bulk density" is that it can vary enormously (granules of the powder can be different sizes) from one measuring session to the next and the amount that the powder is "packed" in the measuring container (i.e. a measuring spoon) varies as well. I have been told it is very hard to accurately measure amounts within 15-20% of the target amount with any consistency using the measuring spoon method.

    And wait, it gets worse ...

    There are several chemicals that are found in needle-like crystals. For these substances it is almost impossible to get within 50% of the target amount with any consistency. To make matters even worse, substances that fall into this category are those where extreme accuracy if required to obtain good amounts (e.g. BZT - you don't want to go overboard on this stuff!).

    On occasion, some have mentioned that some chemicals that are hygroscopic are best measured using volumetric means because they absorb moisture from the air and the amount weighed on the scale will be inaccurate. That would be true - if one repeatedly opened the container of contents to withdraw amounts of the material. The way around this is to simply buy small amounts of the material (yes - it's more expensive this way) and mix the entire contents in solution at once. Mercifully, there are relatively few substances that fall into this category.

    I used to use the measuring spoon method. Due to the problems cited (and verified by my own personal experience) I no longer do so and my results are the better for it.

  7. #27
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    I have two accurate balances. I can weigh small amounts to the grain and large amounts to the 1/10 gram. I wrote an article in 1973 called "Kitchen Tested Soups" in which I measured ten teaspoons each of various chemicals, weighing each and getting averages and standard deviations. The standard deveiations were no more than 1/10 gram. Next I mixed up D-76 using accurately weighed amounts and different teaspoon formulas varying the amounts of metol, hydroquinone and borax by 1/4 teaspoon in a planned experiment to see how much tolerance there might be for differences between measurements by weight and by volume. If you look closely in "The Darkroom Cookbook" you will see a number of formulas for developers similar to D-76 that differ by greater amounts than you would expect from using teaspoons. I will never convince you who doubt me, but that is not my aim in life. If I can give someone a simple and consistent formula that does not need a balance, let alone one that weighs to the milligram, the balance can come later.

    I concluded that for the developers I tested, the use of volume measurements would not affect the consistency of the results. I would not recommend it for quantitative analysis or basic research, but with proper precautions, it works fine.

    You suggest using stock solutions of certain hygroscopic chemicals. The same concept can be and is applied to complete developers. Take your supposed and in some cases that I have tested, imaginary, errors and divide them by 50 or 100 to see how fine a balance you would need to measure out the chemicals for a single batch of working solution of some of the developers we use.
    Gadget Gainer

  8. #28
    Ian Grant's Avatar
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    Quote Originally Posted by peters
    Arigram-you'd do better to get yourself a copy of the Photo-Lab iindex. Most of the info in the darkroom cookbook was taken directly from that journal.
    Thanks for that I nearly bit for a copy of the Darkroom cookbook today on Ebay.

    Just remembered thanks to your post that I bought the Photo-Lab index a few years ago, I'll go and dig it out

  9. #29
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    while spoons are not very good measn to measure phenidone or sub-gram compounds, they work fine for sulfuite, carbonate, vitamin C, etc.

    Yet, when in need they can be used.
    Mama took my APX away.....

  10. #30

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    Thanks for the response, and I am aware of your position on the matter from the Ascorbate Developers article on the unblinkingeye.com site. I don't wholly disagree with it - but I have some particular concerns of my own.

    In essence, I think there's a happy place between the imprecision of volumetric measurements and splurging 200+ USD for a balance that is accurate to 0.1 mg. I'd like to think I've found a home in that place, so here goes:

    Agreed - there are many close relatives of D-76 that can be "accidentally" produced by introducing the measuring errors associated with volumetric measures of chemicals - and yet give perfrectly agreeable results. Even so, when I wish to produce a batch D-76 I'd like the finished result to be just that - not Ansco 17 which it is perfectly possible to produce unintenitionally through measurement errors. As I focus on the 35 mm format (at least for now) these inconsistencies might be, occasionally, sufficient to show up in an 7X enlargement.

    Regarding the expenditure for a balance - it is perfectly possible to acquire one for $40 USD (Lyamn Pro Series) that is going to be accurate to within about 5 mg or so. This is perfrectly acceptable accuracy for me and dramatically better than I get with my $3, $7, or $9 measuring spoons.

    And on the topic of measuring spoons - an experiment I performed a few weeks back suggested that both the accuracy of the smaller sized spoons is flawed; a completely separate concern from the bulk density matter. My experiment was very simple and consisted of filling the 1/16 tsp spoon with water and decanting it into a small graduate. I repeated this action 16 times and then attempted to decant the graduate into the 1 tsp spoon. I performed this experiment 3 times with each of my 3 mixing spoon sets, and I found that each set produced between 1/8 and 1/4 tsp MORE than the expected 1 tsp of liquid. Admittedly, surface tension could play a bit of a role here as I'm measuring out a liquid - but I consciously tried to avoid over-filling the spoon. This particular issue only appears to pose a concern for the smallest of spoon volumes (e.g. 1/16 tsp) - but since I'm often concerned with these amounts for restrainers - where an error can leave me with higher base fog (a royal P.I.T.A. for my paritcular paper and light source combo.) or degraded sharpness, contrast, and film speed, I consider the $40 to be well spent.

    Regarding your last point - I do try to avoid working in very small amounts. When a formula calls for something like 1% BZT I'll try mixing a couple liters of the solution to minimize the loss of accuracy introduced by the smaller amount comforted in the fact that it will likely keep for some time. Where Phenidone is concerned I try to avoid mixing formulas that call for less than 0.5 g. And in any case, I'm a heck of a lot more comfortable weighing this out on a balance accurate to 5 mg (1%) vs. the perhaps 50 mg inaccuracy introduced by the spoon. Fortunately, your own PC-TEA formula has allowed me to circumvent this matter entirely, as I now produce 1 L of PC-TEA stock which contains a much easier to amount of 2.5g. I've also had the good fortune to avoid having to use hygroscopic chemicals, such as Sodium Carbonate or Sodium Hydroxide, for my mixing activities.

    My personal belief is that if one really doesn't have the means to procure an adequate balance - which shouldn't really be cost prohibitive or very complex to use - and one has only volumetric measuring means at his/her disposal, I think it would be best to consider restricting one's mixing activities to producing Rodinal, PC-TEA or similar formulas that are highly-concentrated, have long shelf-life, and are therefore likely to offer the maker some guarantee of consistent (if not optimal) results.

    On the other hand, if one is going to be producing a batch of only 1 liter of D-23 or D-76H stock using volumetric means - it's going to be difficult to achieve consistency from batch to batch.

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