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  1. #31

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    A short note: selenium toning the negative also increases granularity and it may not be desirable. If this route is chosen, test with a test film of the same emulsion processed identically to see if the quality is adequate. I'd rather use the method I described before in this thread.

    Generally, if there is something wrong and bad enough so that sufficient correction cannot be made during printing process, it's a good idea to get a high quality scan of the negative and just deal with that... but this original post does not sound bad enough to touch the negative.

  2. #32

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    Lots of good advice given which is why forums such as APUG are so valuable. The print in question has good blacks, slightly soft mid tones and highlights. If I increase exposure/development the middle grays become darker. I don't want middle grey tones to darken as the subject primarily is in the middle register. Those greys need more contrast.

    Your comments got me into a book I own, Controls in Black and White Photography. Richard Henry writes about one experiment extending development times in Dektol. His conclusion was extending development time only provides a small (13%) increase in contrast. Last night I adjusted exposure and increased time to 3 min. There was not much of a change.

    Switching to a condensor is an option. I have access to a B-22 at a local community darkroom but they don't have a 645 neg carrier. I have two enlargers at home, a 1C and LPL C7700MX w Color head.

    I'm going through all this trouble to find new paper materials. Galerie has a different paper curve than other papers I use. One paper is not better than the other, just different. Galerie has excellent mid tones and a long scale.
    RJ

  3. #33

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    Richard, based on what you just said, I suggest to print slightly darker, develop fully, and use a dilute ferricyanide bleach to lighten highlights and lighter midtone, and then re-fix, wash and whatever your usual sequence. If you don't completely re-fix and tone it in polysulfide or selenium, you get interesting effects but that's another story. I use this technique a lot when doing portrait work and when the skin tone is a bit too dark to my taste (given the contrast and density of other things set right).

  4. #34
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    I mixed some paper developer in warm water (100F) and didn't let it cool long enough - I noticed a big jump in contrast (kind of subjective - didn't actually measure it) - I already use a condenser enlarger - I like the sharper images! hate the sharper dust though.
    My photos are always without all that distracting color ...

  5. #35

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    Years ago I remember that in a Howard Bond workshop he recommended using Edwal-G print developer to increase contrast slightly. I tried it once but can't recall the results. In those days you could get the higher grades of paper and I found it easier to go down. Now I'd just use VC for those things that don't print well on the available grades.

  6. #36

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    Quote Originally Posted by fhovie View Post
    I mixed some paper developer in warm water (100F)
    and didn't let it cool long enough - I noticed a big
    jump in contrast ...
    I think that is due to an increase in activity of any
    hydroquinone present in the developer. IIRC it is more
    active than other agents at elevated temperatures and
    the more so with the more exposed portions of the emulsion.

    I had forgotten about that. Could be a good trick
    for boosting contrast. Dan

  7. #37

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    The activity of hydroquinone goes up as the temperature is raised but this doesn't necessarily increase contrast. It's likely not in the case of most print developers. As long as an electron transfer agent (Phenidone or Metol) is present, increased temperature increases the overall rate of development.

    If a developer is to be reformulated for a different temperature, the ratio of the developing agents, etc. should be adjusted for optimal superadditivity. Also, at a higher temperature, fog formation is increased, so this, too, needs adjustment.

  8. #38
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    I believe the heated developer was actually PC-TEA. So the agents would be Phenidone and Ascorbic acid - The contrast boost was my initial impression - I did not compare results with identical prints done in the same batch, later - cooler - It just seemed to me like it was a big unexpected contrast jump for the apparent DR of the negative I was printing at the time.
    My photos are always without all that distracting color ...

  9. #39
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  10. #40

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    [QUOTES=Ryuji;472085]
    "The activity of hydroquinone goes up as the temperature
    is raised but this doesn't necessarily increase contrast."

    It is common knowledge that developing agents are more
    active at higher temperatures. There are NO exceptions of
    which I'm aware. That increase in activity is not the same
    for each agent. True or false? Actual data I do not have;
    from reading that is my impression.

    As an agent alone hydroquinone either does or does not
    produce an increase in contrast with an increase in
    temperature. Easy enough to test.

    "It's likely not in the case of most print developers. As long
    as an electron transfer agent (Phenidone or Metol) is present,
    increased temperature increases the overall rate of development."

    And the most active of the agents at that increased temperature
    will the more influence development. After all hydroquinone at
    normal temperatures IS a developing agent and I suspect
    that at elevated temperatures, much more active.

    "If a developer is to be reformulated for a different temperature,
    the ratio of the developing agents, etc. should be adjusted for
    optimal superadditivity."

    That statement only supports my contention. The increase in
    activity of the various developing agents with increase in
    temperature is NOT the same.

    Optimal superadditivity is a secondary consideration when
    formulating developers. A lot of popular film and print
    developers have no superadditivity at all or deviate
    greatly from those 'correct' ratios. Dan

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