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  1. #11
    MattKing's Avatar
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    The shorter rolls are less likely to run up against the capacity limits - if 100ml of stock is minimum for 36 exposure, then 75ml is probably fine for 24 exposure (the ratio isn't strictly linear, because while the exposed frames have 2/3 the area, the leaders are the same).

    This means that if you are trying to use 1 + 2, you will be able to fit it into a 250 ml tank (75ml + 150 ml = 225 ml, whereas 100 ml + 200 ml = 300 ml).

    And Jeff, the 120 roll in your RB67 requires the same developer as a 36 exposure roll of 135. Whether you are shooting with a 6 x 4.5 back, 6 x 7 back or 6 x 8 back, it is the same amount of film .
    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

  2. #12

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    Roger, connections were made between the "XTOL failure syndrome" and dilutions greater than 1+1, particularly when using tap water. It has never been clear to me why that would be the case. Based on everything I've read on the subject Kodak traced the failure problem to the packaging for 1L packets (which is why you can only buy 5L packets now). My guess is Kodak would prefer you stick with stronger dilutions so that you use more developer . Personally I've never had a problem with 1+3. Just make sure you use a decent total volume.
    Last edited by Michael R 1974; 12-03-2011 at 02:37 PM. Click to view previous post history. Reason: Clarity

  3. #13
    Roger Cole's Avatar
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    Yeah, I agree it shouldn't have anything to do with dilution. I hated Xtol for years after it came out because I bought some 1L packs and got think almost blank negatives, using 1+1. I tried more than one pack and mixed it with distilled water so I just concluded (even though I had heard of it being bad) that Xtol sucked, at least for me. I tried it again years later and it worked fine, but I don't really want to mix 5L of developer from powder.

    The formula, or something very close to it, is pretty much an open secret and at least one company makes what they say is an "equivalent" developer - but they only sell it in 5L packs too. Someone should package it in something smaller.

    I've never replenished developer. My darkroom usage is spastic and unpredictable with my schedule, so for me diluted one shot is a much better idea (except for Diafine which I do use and which just keeps working and working.)

  4. #14
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    Quote Originally Posted by foc View Post
    When developing B&W 35mm films it doesn't matter if they are 24 or 36 exp. If you developing tank says 300ml for 1 film then you use 150ml of water and 150ml of Xtol (1+1) or 200ml of water and 100ml of Xtol (1+3).
    1:3 is one part developer to 3 parts water. For 300 ml, you use 75 ml of developer and 225 ml of water for a 1:3 dilution, which some would claim is not enough volume of developer for a 36 exp roll. I make no such claim, just pointing out that some do, nor do I have an opinion on whether dilution of Xtol beyond 1:1 is a good or bad thing. I usually mix my own developers and have many opinions about them, but this probably isn't the place to air them. :-)

    Ulysses

  5. #15

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    I really appreciate all the advice guys. Steve been there done that on declaring free agency. I may refer to her as she who must be obeyed or The Redhead From Hell but she is a keeper. I have considered replenished xtol and understand the benefits but as eddy pointed out I am just starting to do this and want to keep it as simple as I can at first. I'll probably give replenishing a try once I can get consistent results I like at a given dilution and time. I will be developing single rolls in a 2 roll tank with a total of 400 ml of solution and a second empty reel to take up the extra space.

  6. #16

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    Quote Originally Posted by Roger Cole View Post
    Why? Is this a general "follow the instructions" rule of thumb (in which case I heartily don't agree, though agree it's usually a good place to start) or based on some negative experience with Xtol diluted more than 1+1?
    Xtol now contains a chelating agent DTPA to prevent a particular form of oxidation which can cause the "sudden death syndrome." Remember when you dilute Xtol you are also reducing the amount of chelating agent. It may be that dilutions greater than 1+1 lower the effectiveness of the chelating agent thus hastening oxidation.

    There is also a peculiarity about ascorbic acid as a developing agent. Remember it is used to replace hydroquinone. The oxidation product of hydroquinone (hydroquinone monosulfonate) is also a developing agent albeit weaker than the parent compound. Then too the oxidation of hydroquinone causes an increase on pH increasing the developer activity. However, the oxidation product of ascorbic acid has no action as a developer. In fact it actually inhibits development by lowering the pH. So there is a double whammy -- oxidation not only removes developong agent from the solution but it also lowers the pH resulting in less development. This difference in the chemistry of the two developing agents is one of the reasons why Xtol behaves differently from D-76 or such developers as Microphen.

    A good source of information is at www.covingtoninnovations.com/xtol.

    Jerry
    Last edited by Gerald C Koch; 12-04-2011 at 01:11 AM. 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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  7. #17

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    Quote Originally Posted by ulysses View Post
    1:3 is one part developer to 3 parts water.
    To many people 1:3 means 1 part to make a total of 3 parts or 1+2. This why it is better to use the unambiguous notation using the plus sign '+' rather than the colon ':'.
    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

  8. #18
    Roger Cole's Avatar
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    Quote Originally Posted by Gerald C Koch View Post
    Xtol now contains a chelating agent DTPA to prevent a particular form of oxidation which can cause the "sudden death syndrome." Remember when you dilute Xtol you are also reducing the amount of chelating agent. It may be that dilutions greater than 1+1 lower the effectiveness of the chelating agent thus hastening oxidation.

    There is also a peculiarity about ascorbic acid as a developing agent. Remember it is used to replace hydroquinone. The oxidation product of hydroquinone (hydroquinone monosulfonate) is also a developing agent albeit weaker than the parent compound. Then too the oxidation of hydroquinone causes an increase on pH increasing the developer activity. However, the oxidation product of ascorbic acid has no action as a developer. In fact it actually inhibits development by lowering the pH. So there is a double whammy -- oxidation not only removes developong agent from the solution but it also lowers the pH resulting in less development. This difference in the chemistry of the two developing agents is one of the reasons why Xtol behaves differently from D-76 or such developers as Microphen.

    A good source of information is at www.covingtoninnovations.com/xtol.

    Jerry
    Thanks. That would seem to make good sense as far as not over diluting the stock (in fact it makes me wonder if it could be UNDERDILUTED to good effect on longevity - dissolved in only as much water as it takes to fully dissolve the powder then diluted accordingly when used as a one shot working solution) but I wouldn't expect dilution for one shot use just prior to development would have any effect on oxidation, unless it oxidizes very, very quickly at that dilution or, probably more likely, it makes it more prone to exhaustion during development? But I'd think one could work around that by just using more solution, given sufficient agitation.

    In any case I don't use it right now but I will keep this in mind if I try it again in the future.

  9. #19
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    Quote Originally Posted by Sirius Glass View Post
    There is no logical reason to take the clear and direct annotation of 1:3 and obfuscating the meaning by using 1+2, unless the goal is to befuddle others out of pure meanness.
    1:3 means 1 part to three parts and not 1 part into a total of three parts; "1:3 means 1 part to three parts" is used in chemistry books and cook books.
    Most chemists would disagree.

    Granted in photography we have long used 1:3 to mean one part concentrate or stock to three parts water. But in chemistry, and thus to some coming to photography from other fields, it's confusing because it means exactly what the post you were responding to said (in fact I had started to point that out myself but every time I do, a weird argument ensues.)

    I always prefer the 1+3 nonemnclature because it's clear and unmistakable to BOTH groups - people who only know darkroom work and those coming from other fields that involve mixing solutions.

    EDIT: Or, I notice you say it means the same in chemistry. When I took high school chemistry in 1980 and college freshman chemistry a couple of years later 1:3 meant one part in a total of three parts. Maybe that convention has changed since. Never the less, no one mistakes 1+3 while some might mistake the meaning of 1:3.

  10. #20

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    Here we go again...

    The ":" can be used to indicate either a ratio or a factor, depending on the commonly-accepted use in the particular field in question. You have dilution ratio (1:3 = 4 parts total) or dilution factor (1:3 = 3 parts total). Basically, only scientists use dilution factor. Pretty much all laymen (and photographers) use it to indicate a ratio; that is what ":" is commonly understood to be in "real world" use. So there should be no confusion in the matter...but if there is, a closer read of the manufacturer's technical data sheets and instructions will clear it up.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

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