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  1. #1
    Sean's Avatar
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    I was wondering if many people make extra exposures during a shoot for different printing techniques. I'd like to dabble in enlarging 8x10 and contact printing probably with some of the same images. It seems wise to expose for a contact print, then take another shot for enlarging. Am I asking for a headache here?

  2. #2
    Ole
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    I usually take two exposures, intending to develop them differently. The exposure is the same. I usually end up giving them the same development, too. Except when I use one for some experiment - like trying a new developer.

    Most of my negatives have plenty of contrast for contact printing and alt.process, and enlarge well with a little chemical trickery.
    -- Ole Tjugen, Luddite Elitist
    Norway

  3. #3
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    Sean, there's been much discussion on this, both here and on the Azo forum. I recommend you peruse the Azo forum (michaeland paula.com) and what's here on APUG. I'm sure you'll find the answers you need.

    In general, it really depends on what type of paper you will print on. Azo, in general, needs higher density than enlarging papers.

    As far as film developing is concerned, if you go through the posts by Sandy King and Don Miller, you will see that the concensus is that Pyrocat HD is probably best for dual-use negs while ABC pyro remains the favorite for strictly contact purposes.

    Again, these are generalities I've gleaned from the various discussions over the last year.

  4. #4

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    Sean,
    One could take one exposure and develop it to a 1.25 density range (high value density minus low value density) and have it fit on grade three Azo. The same negative would be suitable for enlarging at a grade 2 when using a diffusion light source on an enlarger.

    Grade two Azo would require a negative with a higher density range (my tests indicate a 1.60 density range). Both densities that I quoted are when read through the blue channel of a color densitometer. This method of measuring density is important in the event that you are using a pyro developer. The pyro developer stain in the higher densities will add .20 additional density effect when contact printing on Azo and exposing to a conventional flood lamp. If you were to use a light source of higher near band UV output the pyro stain would add additional density effect above what I quoted above. (probably nearly another .10-.15 density units)

    If you are planning on using your new enlarger the densities for this light source would hold true for enlarging on Azo as well. Since pulsed Xenon is fairly heavy in near band UV and blue emission from what I understand. (Azo exposes more rapidly to near band UV).

    Obviously a great deal depends on your film, developer, and light source. Azo does not require greater overall negative density. It does require a negative of higher negative density range. (contrast in other words).

    Not all films are capable of building the density range that Azo accepts. Especially when one gets into expansion of contrast (N+ situations).

    Good luck in your efforts.

  5. #5
    c6h6o3's Avatar
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    Quote Originally Posted by dnmilikan
    Azo does not require greater overall negative density.
    The Azo I use does, especially this new Canadian stuff. It requires a negative with a little more contrast than one optimal for enlarging papers, but a lot more density.

    I rate Efke PL100 at 50, place my shadows on Zone IV and develop for 12-18 minutes in ABC pyro (by inspection). I rate 400TMax at 200, place the shadows on Zone IV and develop a normal negative for 10 minutes, an N+1 for 12 minutes. I do not develop by inspection with TMax.

    The resultant negatives look black when I turn on the lights, but when I print them there's tone everywhere. On the old Rochester grade 2 Azo, some of my Tmax negatives require a 3 minute exposure under a 300W R40 lamp 3.5 feet above the frame.

    Since I've been shooting and developing for extra density in my negatives, the shrugs formerly elicited when I showed people my prints have turned to gasps. Therefore, I'll keep on doing it.

  6. #6

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    If you expose for an enlarger print, then you could use one of the negative duplication routes to get a 2nd negative with increased density for contact printing ( see Ed Buffaloe's Less is More article http://unblinkingeye.com/Articles/NbyR/nbyr.html ).

  7. #7

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    Quote Originally Posted by jdef
    Regarding the difference between greater overall density vs. greater density range; if my low values stay where they are, first density above FB+fog, then how can I extend the contrast range without developing to a higher density in the high values? I can't extend the range downward, right? So wouldn't that suggest a greater overall density? Or do you mean by higher overall density that the lower values are more dense as well?
    Jdep,
    Obviously to extend the density range (contrast) does require one of or quite probably two different things. The first being that of increased developer activity and second longer development time. Not all films are equal in their ability to extend density range.

    It seems that C6H6O3 and I have differing views on what we are experiencing with our camera negatives and Azo. My tests using a transmission densitometer in conjunction with a reflection densitometer indicate a certain density range negative will work with Azo grades two and also a certain camera negative density range will be accomodated by grade three. There is nothing inherently different in this regard then any other photosensitive paper and film combination.

    What C6H6O3 is indicating is that his experience is that a higher overall density in the camera negative is producing prints more meaningful to him in his practice. By this I understand him to say that overexposing and overdeveloping the negative is providing results that he wants.

    My experience is somewhat different in this regard then Jim's experience. My experience indicates that by overexposing film I hinder the ability to build the density range (contrast) that the camera negative can produce. My experience indicates that this keeps me from experiencing all of Azo's long exposure scale potential. The results that I am obtaining are meaningful and satisfactory to me.

    As in all things this is another of those times when things are not clearly defined. What overexposing the film will accomplish is moving the shadow densities up off the toe of the film's characteristic curve. This will provide better shadow value separation. This will, as I indicated earlier, cause a decrease in the overall contrast that the film is capable of producing. Proper exposure of the film will have somewhat lower shadow value tonal separation but will accomplish more in upper value separation. This is due to the fact that the film is recording the information on different portions of the film's characteristic curve. The film if overexposed will tend to place the high values on the shoulder of the film's characteristic curve. This will tend to hinder high value tonal separation as the expense of greater shadow tonal separation.

    Sometimes we get so caught up in discussing things that we tend to discuss terminology rather then practice. I hope that my understanding of practice has been indicated by this.

  8. #8
    lee
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    Don C6H6O3 et al,
    Is this a problem ( the way your both approach this issue differently) caused by two different individuals or is this a problem caused by two different pyro developers? Don is a Pyrocat-HD and C6H6O3 talks about his use of ABC-Pyro.

    lee\c

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    c6h6o3's Avatar
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    The point I failed to make is that I don't think it's possible to produce a negative that's optimal for both enlargement and Azo. One that can be printed on both types with acceptable results, yes. One that will produce the finest prints possible on both media, no. The negatives I make which enlarge well have too much contrast for Azo.

  10. #10

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    Quote Originally Posted by lee
    Don C6H6O3 et al,
    Is this a problem ( the way your both approach this issue differently) caused by two different individuals or is this a problem caused by two different pyro developers? Don is a Pyrocat-HD and C6H6O3 talks about his use of ABC-Pyro.

    lee\c
    My opinion is that there is certainly a difference between these two developers. ABC in my experience is a much more active developer. It is a very good developer and some of my finest negatives prior to Pyrocat were developed in ABC (both for enlarging and for contact printing)...Lee if you remember the postcard that I sent of the street of that small town...that negative was Bergger developed by inspection in ABC. Incredibly sharp and wonderful tonal separation.

    My difficulty with ABC was one of uneven development. That is the problem that Ansel Adams seemed to indicate as well. I have been thinking of retrying ABC with brush development. That may solve the uneven development problem. I would have to say at this point of having used the two developers that the sharpness edge goes to ABC and that the high value tonal separation is slightly better with Pyrocat. The printing exposure times are immaterial to me in working with silver. I understand that for Pt-pd, carbon, etc. that is an entirely different consideration.

    Beyond that I think that the difference that C6H6O3 and I have is one of individual vision apart from the developer difference. Nothing wrong with his ideas...nothing wrong with mine. Just different.

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