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  1. #11
    Stephen Benskin's Avatar
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    Another example is one that I frequently use. If the scene is about a step under normal, I usually will process it normal and print it on a grade three. One of the rules I keep in my head is that processing extends the highlights and printing brings out the mid tones. Most of the time, I'm more interested in having good local separation of the mid tones than a negative that will print on a grade two paper. Both pushing the film +1 and processing it normal and printing it on a higher grade paper will produce the full tonal range, but they produce very different local contrast. This can be graphically depicted in the upper right quadrant of the tone reproduction diagram.

    Along the same lines as the above technique is taking a scene with a normal luminance range and expanding the mid tones with an unsharp mask. I have a good example of this. It was late in the day just after a storm. The sun was moving in and out of the clouds and was coming from a slightly back lite condition. The scene was an iron age broch on the Isle of Lewis, Scotland. The luminance range of the main subject was normal with the assumption that the upper clouds would have to be burned in (I usually don't factor the sky into the exposure calculation). The broch is made of stones of very similar values. Processed normal and printed on a grade two, the "main" subject of the broch would look weak.

    I shot the scene using an orange filter and processed it normal with the intent of using an unsharp mask. The unsharp mask also acts as a contrast mask, so I was able to print the negative on a higher grade and pull out the mid tones. I also did some bleaching in a couple of spots to "pop" them up.
    Last edited by Stephen Benskin; 12-02-2007 at 12:32 AM. Click to view previous post history.

  2. #12

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    Quote Originally Posted by Stephen Benskin
    One of the rules I keep in my head is that processing extends the highlights and printing brings out the mid tones.
    And would you add to that "exposure brings out the shadows"?

    Kirk

  3. #13

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    The shadows in my asked opinion are primarily set by exposure with out much influence from development. The use of the unsharp mask can have a very visible impact on the shadows...depending on mask exposure and mask development.
    If the exposure/development for the unsharp mask is such that it does not allow for any density of the high lights then the mask will have its effect primarily in the shadows and midtones.

  4. #14

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    Quote Originally Posted by Stephen Benskin
    Here's an interesting question. Except for special cirumstances, all scenes look best in a print when there is a full range of tones. Why can't we let a flat scene remain flat in the print (apart from artistic considerations)? It's flat in nature, why not the print? Maybe a question for another thread.
    Should we let a flat scene remain flat in the print? Purely a question of photographic aesthetics that has many answers. Just look at Peter Henry Emerson's platinum prints of the Norfolk Broads for an idea of a photographic aesthetic that is very different from that of today. Emerson, who based much of his theory on the work of Von Helmoltz's Physiological Optics, concluded that it was impossible to reproduce in a photograph the extremes of light and dark found in nature. To compensate for this he recommended a compression of tonal values, which explains why his platinum photographs, and those of several generations of pictorialists, have a very flat look.

    Anyone with a little time on their hands and interested in why we print the way we do might find his Naturalistic Photography for Students of the Arts an interesting read.

    Sandy

  5. #15

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    To repeat something I wrote in another thread, the issue of SBRs of less than 5 is for all practical purposes a mute question for photographers contact printing with in-camera ULF negatives on AZO #2 and many alternative processes, including albumen, carbon, kallitype, platinum and palladium and Vandyke. These processes have log exposure scales on the order of 1.5 to 2.2 and even normal SBR of 7 require negatives with a CI of .75 and higher.

    In reality very few films available in ULF have enough expansion capability to reach even SBR 5 when the CI even for normal SBR is so high. Ilford FP4+ and Efke PL 100 just make the grade but nothing else comes close.

    What to do if you print with alternative processes with in-cameras ULF negatives? Well, no point to obsess about exposure technique for potential SBR values below 5 since the available films won’t allow it anyway. The only option is to expose the film at the lowest SBR value your film/developer combination is capable of, which you would have determined from previous tests, and then use process controls to give the contrast desired on the print.

    As for the broader issue of Zone System versus BTZS, this is pretty much a non-issue for me. I use them both, depending on conditions. In fact, before I discovered BTZS I had been using Zone System for the better part of two decades. At this point, however, I will say that I prefer BTZS for about 90% of my work. But there are a few conditions where Zone is easier to use. If you have actually used both in the field you will, or should, understand this.

    Sandy
    Last edited by sanking; 04-16-2005 at 12:04 AM. Click to view previous post history.

  6. #16
    Stephen Benskin's Avatar
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    Quote Originally Posted by sanking
    What to do if you print with alternative processes with in-cameras ULF negatives? Well, no point to obsess about exposure technique for potential SBR values below 5 since the available films won’t allow it anyway. The only option is to expose the film at the lowest SBR value your film/developer combination is capable of, which you would have determined from previous tests, and then use process controls to give the contrast desired on the print.
    King touches on another potentially interesting question that might be a good topic for a whole new thread, and that is about the conditions of the aesthetic criteria of alternative processes. Is there another set of aesthetic criteria inherent in different processes. There are for transparency film depending on the viewing conditions, i.e. viewing a projection or viewing the image on a lightbox. And transparencies have a very different set of criteria than print, so it should be fair to say that different processes within "black and white" will have different aesthetic criteria associated with it too.

    Keeping on topic, take Michael Kenna's work. He currently likes to make dark somber prints that aren't too contrasty and with a nice brownish tone. It's beautiful work no doubt about it. But would the prints be as acceptable if the tone was neutral? I believe he is able to print darker because color adds an additional element to the print, one that adds an additional dimension of mood, while a neutral print only has tones to work with. The additional "mood" makes up for lost shadow detail. In a way, his black and white images can be thought of a color images and there is a definitely a different set of criteria with color than black and white. My point is the use of color or alternative processes can also be a way of dealing with the presentation of luminance ranges.

  7. #17

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    I do get a bit confused with the way that you use the SBR terminology Sandy. Coirrect my thinking: SBR is BTZS Incident system terminology. An SBR of 5 is a flatly lit plane without any lighting variation. I get that impression that when you say SBR 5 that you are referring to 5 stops of difference in lighting ratios between lit and shadowed areas instead of no difference. I am no stickler for terminology but if each of us means something different when using the same term the communications of concepts and ideas can get quite muddled.

    I also believe that SBR is a term that applies only to a scene.

  8. #18
    Stephen Benskin's Avatar
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    Jay, I'm not going to touch BTZS use of terminology, but Subject Luminance Range does only refer to the scene. The luminance from the scene is then illuminant upon the film after it enters the camera. At which point it is referred to as the exposure E, the amount of light falling on the film in one second, or the photographic exposure H with represents the exact amount of light striking the film in a given exposure. Remember the old I x t = E? It's now E x t = H. Exposure times time equals photographic exposure. This equation is good for either sensitometric exposure or camera exposure. Of course, finding E is a whole other story.

    My concern about Davis' use of the different terms is that while it works within the limited number of people using BTZS, it creates confusion when attempting to communicate the ideas to the outside community. My personal opinion why Davis uses such outdated terms such as SBR and ES is because they were used in the seminal papers Davis must have read when learning theory. He used them in the first edition and then was stuck, so in the later editions he was forced to use a disclaimer. Personally, I think he should have corrected the terminology before it became too engrained. Note: The BTZS part is just conjecture and opinion, so please do not consider it a call to arms.

  9. #19
    Stephen Benskin's Avatar
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    Quote Originally Posted by jdef
    Can the SLR/LSLR be measured with a spotmeter? Further, if SBR exists only in the scene, how is it derived from a curve? If the value found by Davis' SBR calculation is not truly SBR or SLR/LSLR, what is it/should it be called?
    Jay
    Of course subject luminance range can be measured with a spotmeter. In fact, you can only assume the range with an incident meter. There's an interesting paper by Jack Dunn entitled Expose for the Middle where he talks about how an incident meter is perfect for the criteria of the transparency.

    When you are talking about the curve you are talking about the range of exposure (H) usually referred to as log-H range or sometimes LHR. LSLR basically becomes the log-H range in the camera. Your right in thinking that the two are associated with each other.

  10. #20

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    Jay i would interpet it this way. The stepwedge useage tells you what your materials are capable of with different exposure and development for both film and paper. When dealing with the stepwedges you are not at that time dealing with either zones or SBR. That basic data is used in either application to zone system work or incident system work. The SBR is only referenced to the incident system and does not deal whatsoever with the zone system. Go to your BTZS manual and see if you can find with the zone system the usage of the term SBR. Go to the incident system and I am certain that you will find it being used with regularity.

    Of course Claire may have egg colored face if you find such a case.

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