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  1. #21
    Athiril's Avatar
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    Quote Originally Posted by markbarendt View Post
    So, I take it that your example is a negative scan.

    Can we assume also that you tweaked the scanned file a bit electronically to wring out that extra detail?
    No, it is just setting black and white points, nothing else. You lose a lot of detail on a flatbed scan compared to a print.

    Regardless, lightjet prints are far more relevant for film users, the majority of prints made from film are not from a traditional larger.

    If I were to 'tweak' it I would have restrained the highlights from clipping. You would treat this as a low-contrast neg in an enlarger and get the same result above, though not the same since a print is reflective with better blacks and monitor backlit with better whites.

  2. #22
    Nicholas Lindan's Avatar
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    Pushing works best with uniformly lit low contrast subject matter. Unfortunately, most pushers try it with very contrasty lighting like street lights or stage lighting and the results are (to my sensibilities) execrable. Stage and street lighting should be pulled - Tri-x exposed at ASA 50 and underdeveloped by 50%.

    I think the reason for using 'green light' is convenience: most older photographer's still have their Brownie safelight kit with the dark green filter dome. It gives a good consistent source of very dim light.
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  3. #23
    2F/2F's Avatar
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    Of course pushing works best with low contrast subject matter. That is almost always ideal if you must push.

    But in the real world, where pushing mostly takes place out of necessity for a hand-holdable shutter speed, things are highly variable and usually completely beyond our control. Try rating your Tri-X at EI 50 shooting a performance hand held in contrasty (but very dim) light, and you will find that you have zero or close to zero usable shots, due to motion blur and/or camera shake and/or missed focus combined with lack of D of F. The occasional shot that might work will be one in which motion blur works well in the picture. If you could shoot it at EI 50, you wouldn't be thinking about pushing anyhow, so I don't understand the reason for that suggestion unless discussing shooting on a tripod...and again, why would you underexpose 6 or 7 stops if on a tripod?

    If you underexpose your shots and push the film, you incease the density and contrast in the areas where it really matters most – the mid tones – and you get usable shots, which is the goal. You may give up ideal shadows and highlights in order to gain acceptable mid tones. But that is the choice you make in order to get a shot at all. You can avoid white highlights on the print mainly by not including them in the composition in the first place, and you can also do a lot about them in printing. That is assuming that they are truly unacceptable, which they rarely are to me. Lucky for me, a lot of the subject matter that requires pushing also works very well as high-contrast imagery IMO.

    There is always a compromise made somewhere when you cannot get the ideal exposure, but there is always a least-bad option to take. Trying to force standard technical parameters into a situation that is that heavily non-ideal will lead to no pictures at all. So you may as well not shoot hand held in low light in the first place if you insist on having the standard textbook print as the primary guiding principle. You'll get the same number of usable pictures (zero) and you won't waste your time and money.

    Of course, the key to knowing when to push and when not to push lies in your judgment of the lighting in which you shot. It is hard to make statements about pushing that work for all cases of underexposure. Like I mentioned a few posts back, if you are underexposing in order to get a shot over no shot, you should push differently in different types of light. Stand develop – push the low tones while simultaneously pulling the high ones – for contrasty light, and use normal agitation in low contrast light.
    Last edited by 2F/2F; 07-05-2011 at 04:22 AM. Click to view previous post history.
    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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  4. #24
    Athiril's Avatar
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    2F/2F - Pushing this high... I don't think there will be consistent results even from testing a controlled situation, 6400 has consistency on the other hand.

  5. #25
    markbarendt's Avatar
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    Quote Originally Posted by Athiril View Post
    2F/2F - Pushing this high... I don't think there will be consistent results even from testing a controlled situation, 6400 has consistency on the other hand.
    I think the materials and chemicals could be used very consistently.

    What would be tougher is metering and placing exposure at 25000, a push to 6400 being relatively low contrast when compared to a push to 25000, provides a bit more latitude.
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  6. #26

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    Quote Originally Posted by Murray Kelly View Post
    Jerry, I've seen and been told that about the latensification with green light, very dim and very far away. Clair Senft uses it with her Imagelink-HQ and a peroxide latensifier too.

    Nobody has ever told me why it has to be a green light, the peak of human light sensitivity. B&W film is sensitive over a wider range as you know, so why green? TIA
    Murray
    Hi Murray,

    That's a very good question. The books I have read never mention a specific wavelength to use. I assume it doesn't really matter. The sites are going to activated regardless of the wavelength used if it is within the sensitivity of the film. This is a guess but using a green safelight may be only for the users benefit. After setting up the film and the safelight you have to be able to see enough to get out of the room.
    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. #27
    2F/2F's Avatar
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    6400 is a 4 stop push. I would argue that you are not really "pushing to" an EI that high, just that you are underexposing that much, and developing and printing in a certain way to compensate for it. A true four stop push means that something that falls on a Zone IV equivalent density in the case of normal development is pushed up to a Zone VIII equivalent density with overdevelopment. Some common film/dev combos have trouble even getting to a true two stop push (in which a Zone VI fall is pushed up to a Zone VIII equivalent density). Getting a true three or four stop push is near impossible in most film/dev combinations that people use.

    So, beyond a certain point, it is confusing calling it "pushing to such and such EI;" that point would be the point at which you can accurately compensate for highlight underexposure by overdeveloping. Past that point, you are basically just overdeveloping roughly in order to get a printable negative. It cannot really be said that you are "pushing to" a certain EI unless a tone that should have fallen on Zone VIII if normally exposed (but does not do so due to the underexposure caused by downrating) ends up back at Zone VIII density after development.

    I think Athiril made the same point about the inaccuracy of pushing past a certain point in his last post, but I would put the point of accuracy and of true underexposure compensation for the mids and highs well below EI 6400 with Tri-X. I think that anything past or 2,000 or 2,500, and you are basically just developing a lot to help you out; you aren't attaining a true push "to" a certain EI.

    I think it is much easier to discus pushing and avoid confusion if exposure and development are treated as two separate things. That means EIs should not be used in reference to development, only to exposure. Go past a certain point of underexposure/uprating, and you cannot really push "to" a certain EI. You just take desperate development and printing steps in order to salvage an underexposed negative.

    I underexpose films past two stops all the time. It is necessary sometimes, and a lot can be done to dig a print out of such foul negatives, as Athiril has shown. But I don't fool myself in to thinking that I can truly achieve underexposure compensation through development when underexposing past a certain point. So I don't think of development in terms of pushing "to" any particular EI. I try to judge the light and the exposure I was forced to make, and then take development steps that will best give me a printable neg given where things have fallen with exposure. Simply calling this "pushing to" a certain EI is inaccurate and doesn't give this very involved process it the credit it deserves. It oversimplifies the thought processes and gets people thinking they can do things that they cannot.
    Last edited by 2F/2F; 07-05-2011 at 06:00 PM. Click to view previous post history.
    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."

    - Rob Tyner (1944 - 1991)

  8. #28
    BetterSense's Avatar
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    That's what I wanted to say when I made my post, but I wasn't articulate enough to say it.
    f/22 and be there.

  9. #29
    Murray Kelly's Avatar
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    I am sometimes given to wondering if stretching credibility of a film ( to put it another way) would benefit from using microfilm developers. I have no particular evidence of this but to extend the gray scale of a film that has nothing in the shadows (by definition, it seems) would benefit from a developer that suits the pictorial rather than the usual contrasty developers we're talking about for that sort of film.

    I suggest the usual suspects - H&W, Technidol, Soemarko's Lith film dev, and a couple of newer ones presented on PN. I'm sure you can all think of some others.

    What, with a bit of a flash, and some ultra low contrast developer and paper, just maybe one could get a picture at ridiculous EIs?,

    50 years ago, when Tri-X came out there was an article in one of the photo mags on exposing it at 12,000 and how to go about it. Could have been something for a bit of a laff? I tried, and got some shots, with which I was happy. Do 'not' ask me details. Memory hath its limits. I still have the negs.

    I am broadminded enough to think the OP will have some fun and learn a lot even if he has to teach himself.

  10. #30
    michaelbsc's Avatar
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    Quote Originally Posted by Nicholas Lindan View Post
    Pushing works best with uniformly lit low contrast subject matter. Unfortunately, most pushers try it with very contrasty lighting like street lights or stage lighting and the results are (to my sensibilities) execrable. Stage and street lighting should be pulled - Tri-x exposed at ASA 50 and underdeveloped by 50%.
    This really depends on the effect you want.

    For example, I've been monkeying with some night shots, but doing long exposures to get sufficient light. But looking at the results it's clear that what I'm really looking for is *EMPTY* shadows and blown out lights to convey the feeling of night time.

    So what I'm about to decide is that I really do want to push so what would be zones 4-7 in a "normal" scene become zones 2-9 in my image. And I don't care if the street light blows out; that's part of conveying the image.

    Granted that this is a different effect than what you're talking about. But I am relating my findings about "learning" my materials here. I've spent time finding out that my analysis of what I wanted was totally wrong.

    MB
    Michael Batchelor
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    The camera catches light. The photographer catches life.

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