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  1. #11
    TheFlyingCamera's Avatar
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    Here's where to ask him directly:

    http://www.freestylephoto.biz/hutchings.php

  2. #12

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    Well I posted my question on the freestyle board so we'll see what happens.

  3. #13

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    You should probably use a strong red filter on your densitometer for silver density readings, or at least test your densitometer with a red filter to make sure there is no difference with the filter and no filter.

    You may have seen the spectral scans I made several years ago comparing PMK and PyroCat developer stain. From those scans, you can see the stain has little absorbance in red.

  4. #14

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    Hi Kirk, I get your point in the case of PyroCat, but why would a green stain not absorb red? These Delta 100-PMK negatives are fairly green. Granted the particular green leans toward the yellow (as opposed to blue-green), but the stain is much more green than yellow, nothing like the yellowish color I've seen in some ABC negatives.

  5. #15

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    Hi Michael,

    I'm glad that you are looking at staining developers in a critical and studied manner. In the past there has been more wizardry with these developers than in all the Harry Potter books.

    There is also an on-going question concerning stain images stability toward UV and visible light.

    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

  6. #16

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    Hi Gerald, thanks. I guess the thing with me is, I just don't trust everyone's anecdotal evidence - even the formulators themselves. Don't get me wrong I don't want to come off like I'm trashing Gordon Hutchings (by the way I'm also testing WD2D and have been emailing back and forth with Mr. Wimberley who has been very generous with his time so far). I've had some correspondence with Steven Anchell as well regarding a few seemingly contradictory statements in the FDC and DC regarding agitation with staining developers.

    This all started back when I first read The Book of Pyro (after having read Haist etc). What frankly annoyed me was the total lack of clarity and data in a book which is still considered by many to be the bible of Pyro. I read it over and over, and still came away with the same questions regarding things like the over-the-top agitation "requirements", stain characteristics and the effect of the choice of alkali, stain stability, after-development procedures and whether or not they can result in reduced or intensified stain, graininess and the purported "grain masking" effects compared to both solvent and high definition non-staining developers, film speed, variable contrast printing etc.

    There is no data for any of this anywhere that I can find. Suppose I want to use one of these formulas - well, I will never know if I'm getting what I'm supposed to be getting.

    Im only part of the way into this, and already I feel like based on the information I've collected and the data I've accumulated so far, I could write a fairly valuable Second Book of Pyro.

  7. #17
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    Quote Originally Posted by Gerald C Koch View Post
    Hi Michael,

    I'm glad that you are looking at staining developers in a critical and studied manner. In the past there has been more wizardry with these developers than in all the Harry Potter books.

    There is also an on-going question concerning stain images stability toward UV and visible light.

    Jerry

    In many ways you're right, the Pyro books don't help as they have some strange ideas, like soaking fixed films in the spent developer However the simple answer from experience is some are excellent and deliver what the users need.

    The stability issues seem unfounded as many major collections of negatives were made using developers with far higher staining levels, and even half a centuary (or more) later theres still no issues from negatives printed rather a high number of times.

    Ian

  8. #18

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    Hi Ian, it's true, I'd say the issue of archival stability of the dyes would be pretty much at the bottom of my list of concerns, as I believe it should be for most people (assuming adequate storage of negatives that does not lead to premature degradation due to sloppiness)

    After all, with all due respect to everyone here, it is not as though any of our negatives need to outlive us.

  9. #19

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    The only reason I mentioned the light stability was a fairly recent post where a negative was left on a table in sunlight and suffered fading. Part of the negative was covered so the fading was readily visable. As with all dyes a stain image will fade. The question is how fast. Years ago the trick to use with a color slide that was too dark was to expose it to sunlight for awhile. My concern is negatives used in alternative proceseses using sunlight exposure. Will long or multiple exposures cause fading?
    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. #20

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    Very good point. I hadn't even thought about UV processes.

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