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  1. #31

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    Matching CI is not about shaping a curve to alter characteristics. It is about getting a baseline for the comparison of image structure characteristics. If you develop one film to a lower contrast than another, you give it a graininess advantage, for example. Changing CI also effects speed. Incidentally, how do you know HC-110 gives an "upswept" curve in general?

    Noble: I have no specific ax to grind. Photo Techniques was just an example. It's not just magazines. Books by photographers are generally the same. I'm not doubting your sceintific knowledge. What I'm saying is that while developing film may be easy, the science behind it is not, nor is it easy to generate statistically significant data and interpret it properly. The results are often surprising too.

    When you say the graininess relationship between two films will not change based on the developer, how do you know this? For example we know that TMax 100 is finer grained than Delta 100. I found the difference to be narrower when developing in DDX versus XTOL. I also found TMax to be less grainy in XTOL than in Microdol. Am I right? Perhaps, perhaps not. In the Altman/Henn (Kodak) study we discussed recently here, it was found with Tri-X, sharpness was not improved by a variety of Beutler-type developers compared with D-76. Certainly not what one would expect. Continous agitation may or may not have contributed to these results by limiting the formation of adjacency effects, for example.

    This is why the interpretation of photographic tests is exceedingly difficult. You test two films in Rodinal, for example, and a reader might come away with the wrong conclusions.

    Don't get me wrong, I'm not saying what you propose wouldn't be great if it were done properly. What I am saying is that it is very difficult to do and that definitive conclusions are hard to come to. It's not analysis paralysis. It is simply healthy skepticism. In photography, when someone makes a statement about the characteristics of a film, developer, paper etc, we should ask for some sort of evidence.

    Much of the photographic wisdom we accept is based on anecdotal tradition.

    I'm guessing nobody will want to show me any of their test results after all this...
    Last edited by Michael R 1974; 01-25-2013 at 01:17 PM. Click to view previous post history.

  2. #32

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    Quote Originally Posted by Michael R 1974 View Post
    Noble: I have no specific ax to grind. Photo Techniques was just an example. It's not just magazines. Books by photographers are generally the same. I'm not doubting your sceintific knowledge. What I'm saying is that while developing film may be easy, the science behind it is not, nor is it easy to generate statistically significant data and interpret it properly. The results are often surprising too.
    All you have to do is choose the top two or three emulsions at a given ISO and develop them to manufacturer's specifications and one popular alternative. That is a good baseline study that will yield a wealth of information and you can plan future areas of study based on the results. And a chunk of what you present to the reader doesn't even have to be objective. You can lay out samples of all the images and let the reader decide what they prefer.

    Quote Originally Posted by Michael R 1974 View Post
    The results are often surprising too.
    So basically it is like any other scientific experiment.

    Quote Originally Posted by Michael R 1974 View Post
    When you say the graininess relationship between two films will not change based on the developer, how do you know this?
    That was just a hypothetical example. I was saying IF that was true it would become apparent fairly quickly. If the relationship does change then that is a result as well. My point is just do the basic experiment. As long as you are detailed in your description of the experiment and you stick to your protocols you will come away with useful information. The only issue is you must tell people not to over read into results. Take results for what they are. I see that happen a lot when the lay press gets a hold of scientific experiment results. They extrapolate way too far.

    Quote Originally Posted by Michael R 1974 View Post
    What I am saying is that it is very difficult to do and that definitive conclusions are hard to come to.
    Developing 15 rolls of film to manufacturer's specifications is not hard. I don't think anyone that has developed 10 rolls of film would agree with your statement. Results that vary greatly will be obvious and we will be able to draw conclusions. And if they don't vary greatly that is a result as well.
    Last edited by Noble; 01-25-2013 at 02:10 PM. Click to view previous post history.

  3. #33

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    Quote Originally Posted by Arctic amateur View Post
    What I'm interested in is the character, or "feeling", of films. I don't have any specific scene in mind and I'm not searching for a suitable film for a purpose, I want to see what this elusive "character" is simply out of curiosity. If different films have different character, there must be a difference, if subtle, in the final image. Is it the spectral sensitivity? Contrast? Latitude? I can read about differences and kind of understand descriptions of a film's properties, but it's so much easier to understand with two pictures side by side.

    Of course many other things can change the final result, which is why I was trying to say "don't change anything except the film". Difficult, certainly. Perhaps sending the films to a pro lab would make it easier to ensure consistent development?
    hi again arctic amateur

    as i suggested before it isn't just the chemistry and the film but the person using the chemistry and film, that's the other side of the equation. i have given my method of processing film, in a developer to friends ... time, temperature, dilution, agitation scheme, exposure ( in camera ) so they would know what to expect ... and they wrote to me that their film was so contrasty they couldn't even make salt prints with the negatives ... these are the same negatives that when i process the film i enlarge or contact them onto paper without any filtration at all, and the print developer is not dilute to compensate for contrast &c ...

    i think it would be interesting to see what one person can do with the same film and developer to show the limits of a film and developer,
    but i don't think it will be hugely useful, unless the same person who is using these tests to learn about the film +chemistry &c, is the person who has been the one exposing and developing the film.

    i have pretty much given up on developer tests and film tests. i just process everything i do in the same developer for the same amount of time and get negatives i am used to, and look forward to using.

    photography is a strange beast ... one person's trash is another person's treasure

    ( referring to the lomo thread nobel was referring to )
    Ես այլեւս չի պատասխանելու իմ էլեկտրոնային փոստով
    եթե դուք պետք է ինձ դիմեք ինձ միջոցով իմ կայքը կամ բլոգում

  4. #34

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    Quote Originally Posted by jnanian View Post
    as i suggested before it isn't just the chemistry and the film but the person using the chemistry and film, that's the other side of the equation.
    i have given my method of processing film, in a developer to friends ... time, temperature, dilution, agitation scheme, exposure ( in camera )
    so they would know what to expect ... and they wrote to me that their film was so contrasty they couldn't even make salt prints with the negatives ...
    these are the same negatives that when i process the film i enlarge or contact them onto paper without any filtration at all, and the print developer
    is not dilute to compensate for contrast &c ...
    Well gross incompetence will ruin any experiment. Developing film is easy. With little effort most people can get a negative that is reasonable to print. If someone f's up that bad they are an outlier. Either they are using Tech Pan and developing it in undiluted XTOL or that are very incompetent.

  5. #35
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    Quote Originally Posted by Michael R 1974 View Post
    Incidentally, how do you know HC-110 gives an "upswept" curve in general?
    On HC-110 actually my info regarding its curve came from http://www.covingtoninnovations.com/hc110/index.html and threads here and from what I remember of Adams, his books have moved on though so I can't cite that reference.

    I could definitely be wrong.
    Mark Barendt, Ignacio, CO

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

  6. #36

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    Quote Originally Posted by Noble View Post
    Well gross incompetence will ruin any experiment. Developing film is easy. With little effort most people can get a negative that is reasonable to print. If someone f's up that bad they are an outlier. Either they are using Tech Pan and developing it in undiluted XTOL or that are very incompetent.

    he wasn't incompetent or an outlier or inexperienced &c it happened to be a well seasoned photographer ...
    maybe ... the way i shuffle my stack of sheet film is not the same as anyone else ?
    the water i use is different than his was ?
    my or his shutter was firing at a different speed and needed a cla ?

    there are a lot of factors involved ...

  7. #37

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    Quote Originally Posted by jnanian View Post
    photography is a strange beast ... one person's trash is another person's treasure
    +1

  8. #38

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    Quote Originally Posted by jnanian View Post
    he wasn't incompetent or an outlier or inexperienced &c it happened to be a well seasoned photographer ...
    maybe ... the way i shuffle my stack of sheet film is not the same as anyone else ?
    the water i use is different than his was ?
    my or his shutter was firing at a different speed and needed a cla ?

    there are a lot of factors involved ...
    I wasn't trying to insult your friend. I was just making the point that if you buy the usual Ilford, Kodak, Fuji stuff and if you shoot it and develop it as per manufacturers' specifications with fresh developer even if you make a mistake or two in regards to time, temperature, and agitation you should still get something quite usable. This is what I actually said...

    Quote Originally Posted by Noble View Post
    Either they are using Tech Pan and developing it in undiluted XTOL or that are very incompetent.
    The first part of that statement is key. You said that you are using sheet film which implies manual hand held metering and a mechanical shutter on a large format camera. That is your friend's choice. I advise noobs to get a 35mm full auto camera and start off with the manufacturer's specifications. I have never seen anyone screw up with that. I am pretty sure your friend was not developing Ilford 400 shot at box speed developed in fresh D76. As fiddlers we can create all sorts of weird ways to screw up film, but my experiment proposal was to take all that stuff out of the equation and provide a baseline.

    One thing I've learned over the years is that mass market B&W film has quite a bit of latitude. Being off by a half a stop or developing for a minute more or less or agitating a bit more or less usually still yields a pretty decent image. To get the results like you described takes a major screw up with regular run of the mill B&W film. Check out this very forum. How many times does someone say I shot this film and I was off by one or two stops and people just advise to develop normally? Now with weird film and techniques all bets are off.
    Last edited by Noble; 01-26-2013 at 10:41 AM. Click to view previous post history.

  9. #39

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    the funny thing is, noble,
    the recommendation i gave him
    was ansco 130 1:6 72º tray shuffle
    for 8.5 minutes, which is pretty much
    the instructions that were on every can of
    gaf universal developer ( which ansco 130 is a first cousin of ).
    i have been using this developer with those exact times, dilutions and temperatures
    ( every film i process no matter the asa, or exposure ) for about 13 years, maybe more ...

    and like the recommendations on a packet of d76 or xtol i usually suggest the time is a starting point &c.
    i agree, it really isn't rocket science processing a roll of film, or a stack of sheet film,
    but there are factors besides developer and film ...

    when i agitate a small tank i usually spin it and rotate the whole tank infront of me, like a mobius strip ...
    10 seconds / minutes ... i have watched others agitate, they barely move the tank, or they shake the tank
    or they roll it on the sink-floor or countless other agitation methods ... my film, processed for the same time
    and my agitation scheme comes out differently, noticeably different, than the other ways i mentioned ...
    i have a unicolor drum as well, and when i process in that, my film comes out differently than someone's jobo ...
    with the film developing time adjusted for the rotary processor.

    i agree normal development is kind of normal ... but one person's normal might look different than another's.
    maybe the only way these film + developer tests can be helpful is if they are done by one person with the same developing methodology.
    that is what the endless zone system or beyond the zone system ( film tests for personal film speed ) are all about, but in the end
    it is a personal film speed ...

    i think it would be an interesting experiment to have a thread that is only one specific type of film, and people post attachments to it showing
    whatever film and a note as to how it was developed ... granted there will be a million photographs that all look the same, but there will be
    a handful of images on either end of the spectrum that show the extremes the film can handle, so if someone wants extreme grain or extreme tonality
    or both they can see an image like that, and use whatever method stated as a starting point, realizing their results may look nothing like the posted results ...
    maybe that is what the OP was asking for ?

  10. #40

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    Quote Originally Posted by jnanian View Post
    maybe the only way these film + developer tests can be helpful is if they are done by one person with the same developing methodology.
    That is a given. I'm beginning to see what Michael R 1974 was worried about. jnanian, when one conducts a scientific experiment everything is standardized and the only variables are the ones being tested or the ones that can't be feasibly elimnated. Furthermore as I mentioned previously everything is disclosed in detail in the materials and methods section of the published report. Even things like the film's lot number and expiration date are recorded in case the manufacturer later says they had a bad batch. There is no way you would let different people agitate the developing tanks unless they have already been certified as doing it in the exact same manner. As long as sufficient movement of fluid occurred the exact method of agitation is immaterial. What is important is that it is not extreme (shaking a martini), that it is done in the exact same manner each time, and that the exact manner in which it is done is documented. In today's digital world a short clip showing how exactly the agitation was done can even be placed on the web. At most the variables should be film, developer, and length of developing time... at least as far as the developing stage is concerned. Perhaps there are other variables that can't be eliminated that I am overlooking.

    Also I wouldn't use sheet film. That is not the most common type of film used. My inclination is to use medium format film because you still have a nice big negative to work with but it is still a roll film. Medium format film is great because it would be easy to set up your camera and just swap backs with different films. The problem is not every emulsion is made in medium format nor large format for that matter. So again to standardize 35mm across the board is the logical choice. Initially just to keep things reasonable the first experiment should just be with the top sellers at each ISO. But it's nice to standardize on 35mm in case one desires to do future experiments on funky emulsions only available in 35mm.

    Quote Originally Posted by jnanian View Post
    i think it would be an interesting experiment to have a thread that is only one specific type of film, and people post attachments to it showing
    whatever film and a note as to how it was developed ...
    The problem is a lot of us don't do too much darkroom work. You will get a lot of scanned negatives. Scanners, at least of the cheap (<$1,000) variety are black boxes. I have no idea what my scanner does to the information it reads off of my negative so there is no way for me to make a negative to negative comparison. I think there is a software package that is at least capable of holding exposure constant from scan to scan. But the fact remains you still don't know what the exposure was to begin with.

    Check out this site. I use it to see if what I am doing with a new developer is at least reasonable.

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