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  1. #1
    daveandiputra's Avatar
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    Speed gain or loss with developer

    I'm confused with this, how can the use of a developer resulted the gain or loss of film speed? And how to determine what I have with my developer? Examples will be greatly appreciated

    Thanks

    Dave

  2. #2
    ic-racer's Avatar
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    Some developers exploit the entire potential of the film better than others. All things are a compromize and extra speed (1/3 stop or so) may lead to unacceptable grain.

    1/3 of a stop is pretty insignificant in B&W work, so, or all practical purposes development and speed are independent.

  3. #3
    Newt_on_Swings's Avatar
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    Very simple to do with B&W chemicals, just use as more concentrated, or more dilute, or shorter or longer development times. It is easier to pull than push, but pushing with certain developers may not actually give a true boost in speed, may just appear to, with stronger contrast/ edge effects.

  4. #4
    PDH
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    Pushing film is shooting the film at a higher ISO than recommended by the manufactor by increasing the time development time. Tri X 400 rated at 400 stock D76 is about 6.30 at 20C, to shoot at 1600 the time is about 9.5 at 30C, gain increases with a loss of shadow detail. Some film and developers work best at a lower rated ISO such as Tri X rated at 200 or 320 with a decrease in development time to improve shadow detail without blocking the highlights. Tri X rated at 200 and developed in Microdol X 1:1 for 12 mints if rated at 400 then 14mints. When pulled the film as finer grain and better shadows. In the old days film was pushed for working in low light. The new T grain films are more forgiving and can be shot a highter ISO with good results.

  5. #5
    MattKing's Avatar
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    Quote Originally Posted by daveandiputra View Post
    I'm confused with this, how can the use of a developer resulted the gain or loss of film speed? And how to determine what I have with my developer? Examples will be greatly appreciated

    Thanks

    Dave
    There are very complex answers to this question, but here is a try at a simplified one .

    The "speed" of a film is a measure of how much light is necessary to achieve a level of shadow detail at a certain contrast gradient.

    The ISO or "box" speed is a measure of the light sensitivity of the film when tested under very specific standardized conditions and in a developer that behaves in a specific and standardized way.

    Different developers cause the film to build density in different ways.

    Usually, the developers that build the density in ways that, for example, minimize grain, will most likely achieve that density only if the film is exposed to more light than the amount of light required by developers that, for example, maximise edge sharpness (acutance).

    So as a result, the fine grain maximizing developer is said to result in a loss of film speed, while the acutance developer is said to maintain or possibly enhance film speed.

    Some developers are designed to maximise speed (possibly at the expense of other factors). Those developers are said to result in a speed gain, at least in relation to the standardized ISO test developers.

    And for clarity, when you meter and expose the film using a different "speed" rating, you are exposing it using a personal EI (for Exposure Index).

    Hope that helps.
    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

  6. #6

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    I think the OP has asked a very orginal question which I am not sure we have fully answered. If I have a 400 box speed film and take a reflective meter exposure reading then let's say for argument's sake that I will just about get some texture in a zone III area with developer X which isn't a speed increasing developer.

    I now take the same scene at the same exposure in the same light conditions as before but develop in a one third speed increasing developer. Does my zone III now show increased detail and if so at what price?

    Likewise I do the same with a speed reducing developer like Perceptol. Same scene, same exposure, same light conditions. Do I now lose texture in zone III and it becomes closer to zone II and if so at what advantage other than finer grain?

    In short does a speed increasing developer now reveal detail in the shadow areas that a "box speed" developer doesn't and does a speed reducing developer lose shadow detail in the same area of the neg?

    If that wasn't what the OP was asking then it has aroused my curiosity about speed increasing/decreaing developers and their effects on shadow detail in the neg. I do not want to hijack the thread but hope that my questions are relevant to the OP's thread. They are certainly relevant to me

    pentaxuser

  7. #7
    daveandiputra's Avatar
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    Hi all, I understand the concept of pushing and pulling film, I guess the reply from Ic racer and matt corresponds closest to my question
    So let me get this right, say I use triX at box speed of 400 an using a developer that is said to lose at least one stop. Does that mean by using a standard guide dev time I'll be over exposing the film?
    And what test i can do for determine the speed gain/loss Character of my developer? And does the speed gain/loss characteristic of a developer is related to a film type or is it independent?

  8. #8
    daveandiputra's Avatar
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    Quote Originally Posted by pentaxuser View Post
    I think the OP has asked a very orginal question which I am not sure we have fully answered. If I have a 400 box speed film and take a reflective meter exposure reading then let's say for argument's sake that I will just about get some texture in a zone III area with developer X which isn't a speed increasing developer.

    I now take the same scene at the same exposure in the same light conditions as before but develop in a one third speed increasing developer. Does my zone III now show increased detail and if so at what price?

    Likewise I do the same with a speed reducing developer like Perceptol. Same scene, same exposure, same light conditions. Do I now lose texture in zone III and it becomes closer to zone II and if so at what advantage other than finer grain?

    In short does a speed increasing developer now reveal detail in the shadow areas that a "box speed" developer doesn't and does a speed reducing developer lose shadow detail in the same area of the neg?

    If that wasn't what the OP was asking then it has aroused my curiosity about speed increasing/decreaing developers and their effects on shadow detail in the neg. I do not want to hijack the thread but hope that my questions are relevant to the OP's thread. They are certainly relevant to me

    pentaxuser
    Hi, I'm after a more basic explanation on the speed gain/loss characteristic of a developer
    But if someone want to share on Prntaxuser question, that will only helps my understandment on the subject

  9. #9
    Nicholas Lindan's Avatar
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    Development does not change the film speed. Development does change the contrast - overdeveloping increases contrast and underdeveloping decreases contrast.

    If you underexpose your shots, say by setting the light meter to 1,600 for an ASA400 film for a 2-stop underexposure, then the following happens:
    • The shadows end up on the toe of the film curve with very little contrast.
    • The highlights are two stops under-exposed and thin, though at normal local contrast.
    • Overall - from shadows to highlights - the negative is low contrast.


    If you now overdevelop the film so the highlights move up '2 stops' worth of density you will get a negative with:
    • Average overall contrast
    • Improved contrast in the shadows
    • Increased contrast in mid to high tones


    The result is a print that looks sort-of OK in the low tones but blown-out in the high tones. Deep shadow detail will be poor to lacking.

    You can achieve much the same effect by underexposing and then printing the resulting thin negative on a higher contrast paper. Overdeveloping tends to do a better job of restoring shadow contrast than chaning paper contrast. Often the best results can be had by splitting the difference: putting up with thinish negatives and using a slightly higher contrast paper.

    If you are going to be doing a lot of 'push' work you may want to consider flashing the film to get the shadows off of the toe of the film curve.
    Last edited by Nicholas Lindan; 08-22-2011 at 07:01 PM. Click to view previous post history.
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  10. #10
    MattKing's Avatar
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    Quote Originally Posted by daveandiputra View Post
    Hi all, I understand the concept of pushing and pulling film, I guess the reply from Ic racer and matt corresponds closest to my question
    So let me get this right, say I use triX at box speed of 400 an using a developer that is said to lose at least one stop. Does that mean by using a standard guide dev time I'll be over exposing the film?
    And what test i can do for determine the speed gain/loss Character of my developer? And does the speed gain/loss characteristic of a developer is related to a film type or is it independent?
    In a perfect would we would all be able to carefully test every film and developer combination before we take and develop any important photos using them .

    Any enquiry about the developer's effect on speed should really be a relative one.

    Let's say you are a true traditionalist - you are using Tri-X with Microdol-X and you find that using your equipment and processes, you get the best results metering and exposing at an EI equal to the ISO or box speed of 400.

    Now you have been told that use of Microdol-X usually results in a one stop loss of speed as compared to, say, D-76.

    Therefore, based on your experience with your equipment and processes and Microdol-X and the information you have received about the relative effects on film speed of Microdol-X and D-76, you would be well advised to begin your tests of Tri-X in D-76 at or around an EI of 800 (one stop faster than your EI with Microdol-X).

    To determine the speed gain or loss effect of any new developer, it would be best to do something like the following:

    1) photograph a standard and repeatable wide range target with a known combination of film and developer and obtain a good negative that yields a good print - note the EI used;
    2) photograph the same target with the same film and the developer you are comparing. Meter and expose the subject and note the EI used which results in a negative with shadow detail similar to the first negative - contrast and how the highlights are rendered can be adjusted with changes to development time;
    3) double check the results by shooting another roll at the resulting EI and then developing portions of the roll for different times, to try to determine how long to develop in order to obtain the same contrast as in your original standard.

    The relationship between the EI used with your current developer and the EI that results from your test of the new developer will tell you about the speed enhancing effects of each developer.

    A densitometer makes it possible to maximise your accuracy, but visual tests will usually do.
    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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