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  1. #121
    michaelbsc's Avatar
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    Quote Originally Posted by MaximusM3 View Post
    ... until you supply successful images that can back up all the wonderful theories and tech mumbo jumbo.
    So, would "real" scientific information really help us in producing a great print from a Pyro negative
    This is exactly what George Eastman did. He applied scientific principles so that the average Joe could make successful images.

    I would say the success of Kodak in the last century is adequate evidence of this method.

    or the advice of people who may have no clue about it but have printed thousands of negatives from it and can actually give their "professional" opinion?
    ...
    And this is exactly the mechanism Bob used successfully. He's in good company. There is passage in one of the A.A. books about Weston where the supreme geek of photography comments that he was watching Weston work and wondering just what in heaven's name the guy was doing. The final comment was "but the results speak for themselves." Clearly an acceptance by Adams that Weston's methodology was legitimate, even if it wasn't scientifically rigorous.

    IMO it is a mistake to think of this as a zero sum game. Neither approach is wrong.
    Michael Batchelor
    Industrial Informatics, Inc.
    www.industrialinformatics.com

    The camera catches light. The photographer catches life.

  2. #122
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    Gerold , lets talk a bit about the stain.

    My testing without the stain showed very grainy negs, In fact that is why I referenced Avedon series earlier in this thread. I worked with a photographer and used pyro with no stain and the look is good.

    I have used the non used developer after bath, but side by side I did not see any benifits. at the time

    I am and old dog but I am willing to learn new tricks, in fact Steve Sherman and Sandy King would be my go to people if I want to start experimenting again.

    One thing I should say, I am not bullshitting about the amount of pyro film I have printed and I firmly believe if something is not broke , don't try to fix it.


    I wish a few experts on this thread , would explain the tannin effect of a pyro based developer, which all along I have been saying is the most exceptional property of a pyro developer over lets say Xtol , which is the basis of this thread the OP started.

    BTW I am blushing that you think I am intelligent, you are the first person in the world to describe me as this.

  3. #123

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    There is a wonderful scene in the film adaptation of Mark Twain's "A Connecticut Yankee in Kings Arthur's Court." Merlin has discovered gun powder and is attempting to distinguish what components of his recipe are necessary and which are not. After a successful explosion he remarks, "Next time I will leave out the frog." Not putting the negatives back into the used developer is "leaving out the frog."
    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

  4. #124

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    Bob,

    I am not an expert on photograpic chemistry but I am a chemist. I also have been a photographer for 60 years. I have thus tried many things. PE could probably provide some more insights on what is happening. But here goes.

    The principle advantage of a staining developer is that it produces not only a silver image but also a stain image. Compared to a conventional developer less silver needs to be produced to provide the same density and contrast. The stain image is grainless. Becuase of this the overall effect is a less grainy image. Less silver equals less grain. However, if you like dense negatives then this advantage is lost.

    During development a stain is produced in direct proportion to the amount of silver that is reduced. This creates a stain image superimposed on the silver image having similar characteristics to the silver one. The stain is produced from the oxidation products of certain developing agents like pyrogallol, catechol, and hydroquinone. In order for the stain to form the sulfite content of the developer must be low just as it is for color developers. The stain consists of what are known as condensed polyphenols or humic acids. These compounds are highly colored and the stain is permanent. Once formed the stain is no longer effected by either the acid or the sulfite contained in such solutions as fixing baths. Humic acids are only soluble in concentrated solutions of either sodium or potassium hydroxide.

    Now both tannin acid and the stain are condensed polyphenols. Tannic acid has a lower molecular weight than the stain and so is soluble in water. I think we are all familiar with that fact that animal hides can be tanned using tannic acid to make them stronger. A staining developer does the same thing. The chemical collagen in both the gelatine of the emulsion and the animal hides can be tanned thereby hardening them. Some people say that this tanning action prevents the silver grains from migrating and clumping up thus reducing the grain of the negative. With today's prehardened emulsions this alleged benefit may not be as great as in the past when emulsions were rather soft.

    The tanning effect can be seen by the naked eye as it causes the emulsion to shrink producing a relief image. This also produces a refractive effect upon enlarging.
    .
    If the silver is removed from a negative produced by a staining developer the result is a grainless image similar to that produced by color films. Like so many things in photography this can be good or bad. Yes, there is no grain but the human eye may not perceive this image as being sharp. Anyone who has seen large color prints will experience this effect.

    The amount of stain produced varies with the choice of developing agent. Some produce more stain than others. The color of the stain they produce may also be different. The developing agents differ in the conditions under which they produce a stain. Pyrogallol acts like a regular developing agent very similar to Metol in the presence of moderate to high amounts of sulfite producing no stain image.

    I hope this brief description answers some of your questions.

    Jerry
    Last edited by Gerald C Koch; 07-30-2011 at 05:15 PM. 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.

    ~Antoine de Saint-Exupery

  5. #125
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    One of the great things about APUG is that it brings together people like Bob Carnie ("Bob") and Gerald C Koch ("Jerry") to discuss these sorts of things.

    Bob has lots of experience, is both perceptive and intuitive, and understands more about why and how things work then he is willing to let on.

    Jerry is also perceptive and intuitive and also has lots of experience, but is most fascinated with the why and how questions.

    All the rest of us get to go along for the ride, tossing in other bits and pieces where appropriate (and sometimes where not) and generally end up being a fair bit the wiser.

    I've learned a lot from this thread.
    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. #126

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    Matt,

    Thanks, it's my turn to blush. The give and take on APUG is fascinating and we all prosper because of it.

    Jerry
    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

  7. #127
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    Having switched from Xtol to PMK and in the last 3 years, Pyrocat-HD, I find this one of the most fascinating threads in a long time. Both of you have very good insight...I just know for me that the pyro negs are easier to print. Period. Love the look.
    K.S. Klain

  8. #128
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    Truly interesting thread, may have to try Pyro more in the future. Not rushing to buy though, still enjoying DD-X.

    Quote Originally Posted by Gerald C Koch View Post
    I think most people have problems understanding the Zone System, I know I did. Many of the books on the Zone System are not very good teaching aids. I have read others describe the difficulty. Some state that they have suddenly attained an epiphany when everything finally made sense.
    I actually "got" the zone system concepts real quick. What I was at odds with though for a long time was the application.

    The bulk of the zone system examples and discussions and even most exposure discussions I've seen center on landscape and still-life's where shadow & highlight detail actually matter. That isn't always the case, the subject matters.

    Applying the zone system in portraiture for example, where the placement of the face exposure trumps the rest of the frame, is possible but not near as straight forward as shooting to the shadows and measuring contrast range for landscape work.

    Roll film complicates zone system application and understanding too. Practicalities with rolls pushes us away from changes in development.

    Modern metering systems also throw kinks in the understanding, the zone system doesn't live in a vacuum.

    When I came back to photography 6 or 8 years ago I got an L-358 incident meter right off. Since then I've tried every type of metering available and I am capable of applying them all, but when it comes to printing the negs, and once I got a handle on printing and VC paper, I found the ones where I used the incident meter's suggestions at box speed and my normal development regimes for a particular film, almost always print easiest and most pleasing and lack little if any needed detail.

    In that context applying the whole zone system is confusing, there's always the nagging "why bother?" hanging in the air.

    Reading Dunn & Wakefield's exposure manual was a zone system epiphany for me, it taught me where it was appropriate and where other methods could be applied for better result in my work.

    Quote Originally Posted by michaelbsc View Post
    And this is exactly the mechanism Bob used successfully. He's in good company. There is passage in one of the A.A. books about Weston where the supreme geek of photography comments that he was watching Weston work and wondering just what in heaven's name the guy was doing. The final comment was "but the results speak for themselves." Clearly an acceptance by Adams that Weston's methodology was legitimate, even if it wasn't scientifically rigorous.

    IMO it is a mistake to think of this as a zero sum game. Neither approach is wrong.
    My style in life is more like Weston's as described here.

    When I was learning to fly small planes I used to drive my Dad who was already a pilot crazy because I flew more intuitively than procedurally. He expected certain things at certain times, but I'd apply different controls/strategies. The end results were very comparable, nice smooth landings. My Dad's approaches were linear, mine were more, well, artistic. (Just in case you are wondering, my instructor was quite happy with my "style". Always well within the capabilities of the plane and the safety of all concerned.)
    Mark Barendt, Ignacio, CO

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

  9. #129

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    I don't wish to take this thread off topic so this is only an aside. If you have seen Weston's darkroom you would be amazed as to how spartan it really is. No fancy gadgets only what has a real use.
    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

  10. #130
    Bob Carnie's Avatar
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    Thats pretty good description , way beyond what I could say.

    When I first started with Pyro , 1992 -3 period, my conclusions were pretty much that the developing silver was not migrating/blooming and I did the naked bulb test and confirmed that one developer **Hutchings PMK** certainly worked better. this was a huge benifit to me as a printer as I was still using a lot of graded paper at that time and I hated burning in soft muddy highlights to get detail.
    Modern VC paper and split printing were a godsend to me , on top I had the weapon of mass destruction, pyro developer.. remember I was and still doing this as a commercial process and my competitors were not in the ball park with their quick and dirty process techniques that made them fast money but their film was crap... To this day I still charge more for film not processed by my lab as I do not want to fix lazy workers film.
    The rings of relief you talk about were very obvious to me , much like what you see around Transparancies.
    I am not sure if the emulsions of today have changed that much since 92 , maybe they have and the effect is not as much.

    Magic Bullets: I have stated in the past here on APUG about there being none.

    I lied

    Here are a few gems: fresh film: Pyro: Split Printing: distilled water for the dev:Rotary process with and initial hand agitation to prevent mottling: Stand Development: glass carriers: Apo enlarging lenses: laser aligned enlager:Ilford Warmtone: Dektol 1 1:5 : bleach sepia and selinium afterbath.

    the list goes on and on , each worker can add their own secrets that make their work great.

    I have said this before, there is no such thing as the perfect print> A lot of the workers on this site who take printing seriously are at a world class level> historically speaking there are very few printers that are making better prints before us that are coming out of the darkrooms today. What is different is the quality of the image, that is the hard part.
    If you don't believe me go to as many shows , photo collectors collections and look for yourself, the prints are all within reach to all, its the imagery that is king.
    The very best print I have seen in the last couple of years is one owned by Paul Paletti , it is an 11x14 print of a wave coming in to shore, the tonal range, and crispness jumps off the wall.

    So if you accumulate enough good habits, work hard each year on your projects, and have some talent your work will stand out.



    Quote Originally Posted by Gerald C Koch View Post
    Bob,

    I am not an expert on photograpic chemistry but I am a chemist. I also have been a photographer for 60 years. I have thus tried many things. PE could probably provide some more insights on what is happening. But here goes.

    The principle advantage of a staining developer is that it produces not only a silver image but also a stain image. Compared to a conventional developer less silver needs to be produced to provide the same density and contrast. The stain image is grainless. Becuase of this the overall effect is a less grainy image. Less silver equals less grain. However, if you like dense negatives then this advantage is lost.

    The stain is produced from the oxidation products of certain developing agents like pyrogallol, catechol, and hydroquinone. In order for the stain to form the sulfite content of the developer must be low just as it is for color developers. The stain consists of what are known as condensed polyphenols or humic acids. These compounds are highly colored and the stain is permanent. Once formed the stain is no longer effected by either the acid or the sulfite contained in such solutions as fixing baths. Humic acids are only soluble in concentrated solutions of either sodium or potassium hydroxide.

    Now both tannin acid and the stain are condensed polyphenols. Tannic acid has a lower molecular weight than the stain and so is soluble in water. I think we are all familiar with that fact that animal hides can be tanned using tannic acid to make them stronger. A staining developer does the same thing. The chemical collagen in both the gelatine of the emulsion and the animal hides can be tanned thereby hardening them. Some people say that this tanning action prevents the silver grains from migrating and clumping up thus reducing the grain of the negative. With today's prehardened emulsions this alleged benefit may not be as great as in the past when emulsions were rather soft.

    The tanning effect can be seen by the naked eye as it causes the emulsion to shrink producing a relief image. This also produces a refractive effect upon enlarging.
    .
    If the silver is removed from a negative produced by a staining developer the result is a grainless image similar to that produced by color films. Like so many things in photography this can be good or bad. Yes, there is no grain but the human eye may not perceive this image as being sharp. Anyone who has seen large color prints will experience this effect.

    The amount of stain produced varies with the choice of developing agent. Some produce more stain than others. The color of the stain they produce may also be different. The developing agents differ in the conditions under which they produce a stain. Pyrogallol acts like a regular developing agent in the presence of moderate to high amounts of sulfite producing no stain image.

    I hope this brief description answers some of your questions.

    Jerry



 

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