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  1. #11
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    Quote Originally Posted by dancqu View Post
    I wonder what you'd find if two exposed
    the same prints were given 3 and 5 minute
    development. I suspect you have made some
    similar test. Has the additional development
    time made any difference? Dan
    I did JUST that last night. Purely by happenstance, though. And I found I got warmer print color and about 1/3 grade more contrast going for about 5 mins. These are only preliminary observations though and it was hardly a 'controlled' test. I'm looking at my dried tests today and trying to figure out what to make of it. It's no surprise that you get increased density out of a longer dev time. Graded papers (and multis for the most part) always have responded this way... but graded ones more so. Anwyay- I'm going to get to the bottom of this mystery tonight hopefully and I'll let you people know what I find. The warmer print color kind of surprised me though.

  2. #12

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    Quote Originally Posted by Sparky View Post
    I did JUST that last night. Purely by happenstance, though.
    And I found I got warmer print color and about 1/3 grade
    more contrast going for about 5 mins.

    It's no surprise that you get increased density out of
    a longer dev time.
    So increased density as well. Which developer at what
    strength and which Grade of paper? Dan

  3. #13
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    Well - you'll ALWAYS get increased density beyond a few minutes with ANY paper, in my experience. But with that can come fogging too. At any rate - I was just using dektol since my ansco 130 is shot. It's grade 3. I'm not sure about those results now... I tried to replicate - it's very odd really. It could have been the one that was developed for shorter time. They're a slightly different color though just a BIT - but it could WELL be due to turning the lights on too early into the fix...

  4. #14

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    Quote Originally Posted by Sparky View Post
    Well - you'll ALWAYS get increased density beyond a few
    minutes with ANY paper, in my experience. But with that
    can come fogging too. At any rate - I was just using dektol
    since my ansco 130 is shot. It's grade 3. I'm not sure about
    those results now... I tried to replicate - it's very odd really.
    It could have been the one that was developed for shorter
    time. They're a slightly different color though just a BIT
    - but it could WELL be due to turning the lights on
    too early into the fix...
    Just checked back on an article by Phil Davis which he
    wrote for D-Max. He was testing some Forte papers. Papers
    reached a D-Max with 45 seconds development within areas
    of greatest exposure. That agrees with my results as per
    a earlier post. With less exposure D-Max is achieved
    but with more time in the developer. He went as
    far as 180 seconds. My results agree.

    The up-shot of all that is contrast control by using least
    exposure for desired greatest density coupled with extended
    development. Visa-versa for lower contrast; longer exposures
    and shorter development. Phil settled for 90 seconds as results
    were very near maximum contrast.

    Save for achieving maximum contrast, over expose and pull
    process. That is, do not develop to completion. Dan

  5. #15
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    Right - well it gets you on the straight line of the curve. Otherwise you start riding up on the shoulder and getting blocked up shadows again...

  6. #16

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    Quote Originally Posted by Sparky View Post
    SINCE it's graded you mean...? Okay- I'm a graded paper snob... despite popular opinion - I find I get much greater depth and 'snap' out of graded papers - even compared to the most recent species of multigrade papers. Maybe I'm alone in this.
    My intended message is graded paper is not as flexible as VC. However, because of Emaks rich tonality, tone, and resistance to curl, I find I am using Emaks more and more. Great paper.
    RJ

  7. #17

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    Quote Originally Posted by Sparky View Post
    Right - well it gets you on the straight line of the curve.
    Otherwise you start riding up on the shoulder and getting
    blocked up shadows again...
    I take it you are speaking of pull processing. I've pretty
    much come to the conclusion that developing to completion
    is a myth. I'm quite certain that those using 2 to 3 minute
    processing would find their prints very noticeably shy of
    being developed to completion.

    The amount of time to completion depends upon the
    developer and paper. Exposure is not a factor because
    to completion means the development of all image silver.
    For any one combination, development to completion is
    some fixed time prior to the formation of fog.

    Few I'd say have actually tested to completion any
    specific paper/chemistry combinations. I've only
    recently gotten down to it myself. Dan

  8. #18

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    David Vestal's, The Craft of Photography, ISBN 0-06-014497-1, wrote when using extended development one can both increased or decrease contrast by one grade with cold/neutral papers. He used Kodak D-72 & GAF 120 paper developer with Kodak, Dupont and Agfa papers. He wrote on page 248 - 250 that water quality affected outcomes. He recommended exposure compensation as all tones slide darker throughout long developments. A rule of thumb is to give 20 percent less exposure for a 5 min development vs a 2 min one and 20 percent less for a 10 min development vs 5. He recommended fresh developer, clean trays, and low fog paper. He wrote extended print development lowered contrast using NYC water and raised contrast in other locations. I think Richard Henry in his book disagreed that contrast increased significantly using the technique. I'm somewhat of a skeptic that a slight alkalinity of the water used to mix paper developer can make that much difference. I don't use the technique so I can't speak from actual experience.
    Last edited by Richard Jepsen; 06-29-2008 at 11:09 PM. Click to view previous post history.
    RJ

  9. #19

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    RJ, that reference to Mr. Vestal is another example of some
    experienced fellow doing some testing and observing results.

    This specific case is of the most elementary sort dealing with
    exposure time and development time then noting the results.
    Any darkroom worker's short session. I know Mr. Vestal is a
    Much experienced fellow. How much though should we rely
    on other's for assurance? Have we no belief in what our
    own eyes tell us?

    I digress. I've run a couple tests of the nature above mentioned
    and find that extended development can, from at least one
    Currently available paper, Emaks, reduce exposure by at
    least one third and perhaps by as much as half.

    Now that I've the matter well in mind more tests with more
    exact results are in order. I may even mount my step wedge
    for some ballpark contrast comparisons. Dan

  10. #20

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    I've re-read Dr.Richard Henry's, Controls In Black-And-White Photography (1983) and Vestal's book. Richard Henry used scientific methods to challenge statements regarded as gospel. He refuted Vestals claim about alkalinity in water affecting print contrast.

    He writes that Adams and Looten agree that increasing the time of development produces an increase in contrast and decreasing time of development lowers contrast. Henry claims any increase in the contrast by extending development was small. He goes on to discuss apparent contrast to the human eye. He tested real prints with people but mentions the viewers were equating increase contrast with darkening of all picture areas which does not fit the definition on contrast used by photographers.

    He wrote you can compensate within certain limits for underexposure by increasing print development times. The RD increased from 1.74 for 1 min to 1.97 for 8 min, an increase of 13%. Over a span of 8 to 18 sec exposure, a 2-fold variation, he could compensate the print RDs.

    If I read this right, he agrees contrast was increased with the materials he used at the time but the increase is somewhat small. On the other hand there was the sentence about apparent contrast.

    Next time I'm in the darkroom I will try it again. The tired the technique once with Gallerie I got poor results. Now I switch between light sources and tone for contrast control. I'm happy so far with the results.
    Last edited by Richard Jepsen; 07-02-2008 at 12:21 AM. Click to view previous post history.
    RJ

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