EV mode on my L-508? BTZS

Discussion in 'Exposure Discussion' started by Mike A, Mar 11, 2006.

  1. Mike A

    Mike A Member

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    I'm trying BTZS and was wondering.
    Can I use the f stop and shutter speeds that corrispond with the given EV number as I move the f stops up and down the scale of the meter?
    Mike A
     
  2. Donald Miller

    Donald Miller Member

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    Mike,
    Yes, you can. That is what a EV designates...the different given combinations of F stops and shutter speeds that arrive at the same exposure.
     
  3. Mike A

    Mike A Member

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    Thank you Donald.
    Mike A
     
  4. Jorge

    Jorge Inactive

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    Sorry but Donald is wrong, at least if you are using the BTZS the way it was designed. The only thing the meter does is measure the contrast range, the exposures are determined by your tests and combination curves. This is why if you are shooting 400 spedd film it does not matter if you read the EV difference with your meter set at 100 ASA. Once you have obtained your SBR you have to consult the appropiate charts for your specific film tests and developer combination. The SBR curves will give appropiate exposures for your film/developer combination. If you use the f stop/shutter speed combination given by your meter what you are doing is dismissing the most important part of the system.
     
  5. Donald Miller

    Donald Miller Member

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    Jorge,

    Please reread the original question. The answer that I gave was correct for the question that was posed...at least the way that I read it. I think the gentleman was asking if the different shutter speeds and F stops that correspond to each other at a given EV are the same insofar as the exposure given. The answer to that question is still yes.
     
  6. Jorge

    Jorge Inactive

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    Wrong, what he is asking is if he can use the recomended settings by the meter as the shutter speed/ f stop combinations to take the picture, even if he is using the "correct" ASA in the meter most likely they wont correspond to the the f stop/ shutter speed combinations recommended by the SBR chart.

    IN other words, the meter is used only to obtain a SBR, not to obtain f stop/shutter speed combinations. Unless after he takes an SBR reading, he then changes the ASA in the meter to the speed his tests gave him for that film/developer combination and uses the reading for the low value he obtains after he has changed the ASA parameter.
     
  7. Donald Miller

    Donald Miller Member

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    Jorge,

    I realize that you read it differently then what I read it. I still think that the question that the gentleman posed is whether any of the corresponding shutter speeds corresponding to differing F stops will be suitable so long as they correspond to the same EV.

    The meter does do more then determine the SBR Jorge. It also determines the exposure of the scene. SBR alone will only determine a minor deviation in the film ISO (if the SBR is at departure from 7) and the development time of the film based upon tests. The meter still tells what the proper exposure is. I don't think that BTZS equips one to suddenly sense the proper exposure when it arrives on the winds within the ether.

    Irregardless, I will allow you to assume your interpertation if you will allow me my interpertation of the question as it was posed. I can do that without defining you as being wrong. Can you do the same?
     
  8. Jorge

    Jorge Inactive

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    Donald, the meter does not determine the exposure unless you have changed the ASA to those speeds obtained from the film tests This is very basic BTZS information.

    If the question is "can I use all the different f stop/shutter speed combinations for a given EV value?" then the answer is obviously yes, provided the meter has been reset to the speed value obtained in the tests.
     
  9. Donald Miller

    Donald Miller Member

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    Jorge, I don't recall reading anywhere in the original question where the gentleman suggested doing anything other then using the determined ASA. The question was about combinations of shutter speeds and F stops as related to a given EV.

    In response to your statement, if the meter doesn't suggest the proper exposure, who or what the the heck does?
     
  10. John McCallum

    John McCallum Member

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    In relation to the BTZS, the answer is simply - no.

    Donald your answer is incorrect and would be missleading to Mike.
     
  11. Donald Miller

    Donald Miller Member

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    John, For your information I use the BTZS and I wish that you would not cherry pick the question that was posed.

    For your information the question was as follows:

    "I'm trying BTZS and was wondering.
    Can I use the f stop and shutter speeds that corrispond with the given EV number as I move the f stops up and down the scale of the meter?"
    Mike A


    The answer is that there are several shutter speed and f stop combinations that will arrive at the same exposure. To take your answer would be to say that the exposure must be F 5.6 at 1/250 of a second rather then perhaps a more appropriate F 22 at 1/15 second which may be more appropriate to the exposure at hand.

    That as I read the question posed and not condensed as you have done is what the fellow is asking and the answer is that yes the photographer is at discretion to choose the Fstop and or shutter speed that are appropriate to the exposure at hand consistant with the EV that the meter indicates.

    He is indicating this question by the fact that he recognizes that there are other combinations as he alters the Fstop related to the EV on the meter. It is written in plain English.

    That is not at odds with BTZS. I would wonder where the heck this is misleading? Perhaps you can inform me on where this is wrong.
     
  12. John McCallum

    John McCallum Member

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    You gave an absolute answer without the qualification of prior testing/calibration that the BTZS requires.
     
  13. Donald Miller

    Donald Miller Member

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    Jesus Christ John, that is nitpicking...the man indicated that he was attempting to use BTZS and that sort of predicates the response does it not?

    In fact the question does not depend on the use of BTZS...the question could have been posed on the Ansel Adams Zone System or even the Smokey Joes system of Involved Windage and Elevation Inclusion...it is basic photographic knowledge and theory.

    Your position and response is viewed as being small minded and petty.
     
  14. John McCallum

    John McCallum Member

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    I guess it is. Is that not what the BTZS is all about? :tongue:


    (I'm just john).
     
  15. Donald Miller

    Donald Miller Member

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    Considering this comment, I wouldn't even begin to qualify that with a direct response. It would be a literal waste of time.
     
  16. Donald Miller

    Donald Miller Member

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    Perhaps we should offer entrance exams before any and all questions will be considered. Would you like to volunteer for the position to see that academic standards are met prior to presenting the question to the respondents...or do you have the answers to any and all questions posed?

    On the subject of assumptions. It seems to me that if anyone was jumping to erroneous conclusions it might have been that guy in New Zealand. The post stands and the title says BTZS...what more do you want? Maybe to fish out of being a glaring idiot in this instance.
     
  17. Mike A

    Mike A Member

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    Donald, Your interpretation of my some what cryptic question is correct.
    Jorge, I understand your explanation regarding the ASA as well.

    I would have addressed this earlier but I was out photographing.

    Thank you for your responses gentleman,
    Mike
     
  18. Jorge

    Jorge Inactive

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    Oh borther, it gives you the contrast range so you can calculate the SBR, consult your charts (or input them in the palm) and then obtain the appropirate f stop/shutter speed combination based on the proper film speed derived from your tests....got it?
     
  19. Donald Miller

    Donald Miller Member

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    Yes, but the exposure is determined by the EV reading of the meter based on the shadow value...is it not?

    Which brings us back to the initial question. That being the one that apparently I interperted correctly. The answer to which is that any combination of shutter speed and f stop can be used that corresponds to the EV of the determined exposure.

    Now what is it that has not been gotten and who is it that failed to grasp it?
     
  20. Jorge

    Jorge Inactive

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    :rolleyes:
     
  21. John McCallum

    John McCallum Member

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    Aaaaah what the heck ...

    "There are only two kinds of people who are really fascinating: people who know absolutely everything, and people who know absolutely nothing" - Oscar Wilde.

    Donald, you are fascinating.