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  1. #21

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    Here are scans of test strips, identically exposed, and developed with XTOL and PC-Sulfite.
    The XTOL scan:
    Click image for larger version. 

Name:	3-00-XtolNormalLoRes.jpg 
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Size:	359.2 KB 
ID:	43620 And a crop: Click image for larger version. 

Name:	3-00-XtolNormalCrop.jpg 
Views:	73 
Size:	131.1 KB 
ID:	43621

    And the PC-Sulfite scan:
    Click image for larger version. 

Name:	4-08-PCSulfite2p8LoRes.jpg 
Views:	65 
Size:	360.8 KB 
ID:	43618 And a crop: Click image for larger version. 

Name:	4-08-PCSulfite2p8Crop.jpg 
Views:	70 
Size:	127.5 KB 
ID:	43619

    These images are darkish because I set the white-point as high as possible in the scanner, to clip as little data to white as possible (i.e., maximize the dynamic range). The black-point was set to the left side of the histogram (which was always the same). Gamma was 1.5.
    This is part of my camera-collection, lit by the overhead tungsten candelabra. It's hard lighting, which creates plenty of specular reflections to see how the dense part of negatives are doing. Unfortunately, my Coolscan IV ED scanner doesn't have enough dynamic range to cover such specular reflections well (and still show shadow-detail in the neg's), so many reflections clip to white.

    In the crops above, PC-Sulfite appears to have slightly less grain than XTOL. That's not true. In 22X loupes, they seem to have the same grain. The scanner's focus has a little variation, and the film isn't held perfectly flat, so grain is defocussed by unpredictable amounts. To get sharp images of grain, I want to photograph negatives in a microscope.

    Mark Overton

  2. #22

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    I don't know what the advantage of this developer is. You can change the formula and make PC-TEA. This completely eliminates the sulfite and produces a developer with much better keeping qualities. Triethanolamine (TEA) can be heated safely using a water bath. The resulting concentrate, usually used at 1:50, makes a less toxic and versatile working solution.

  3. #23

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    Quote Originally Posted by dynachrome View Post
    I don't know what the advantage of this developer is. You can change the formula and make PC-TEA. This completely eliminates the sulfite and produces a developer with much better keeping qualities. Triethanolamine (TEA) can be heated safely using a water bath. The resulting concentrate, usually used at 1:50, makes a less toxic and versatile working solution.
    Great for those who can get TEA.
    Her in europe, TEA is clos to impossible to get, so we have to resort to other methods of doing this.

  4. #24

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    Quote Originally Posted by albada View Post
    I haven't heard anyone say that they already knew about this formula, so it appears to be new.
    I don't know why you didn't see me saying it. It's not new. It's one of many things that are obvious to any chemist (including myself) but scrapped due to obvious shortcomings.
    Last edited by Ryuji; 12-31-2011 at 08:28 PM. Click to view previous post history.

  5. #25

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    Quote Originally Posted by albada View Post
    Here are scans of test strips, identically exposed, and developed with XTOL and PC-Sulfite.
    The XTOL scan:
    Click image for larger version. 

Name:	3-00-XtolNormalLoRes.jpg 
Views:	57 
Size:	359.2 KB 
ID:	43620 And a crop: Click image for larger version. 

Name:	3-00-XtolNormalCrop.jpg 
Views:	73 
Size:	131.1 KB 
ID:	43621

    And the PC-Sulfite scan:
    Click image for larger version. 

Name:	4-08-PCSulfite2p8LoRes.jpg 
Views:	65 
Size:	360.8 KB 
ID:	43618 And a crop: Click image for larger version. 

Name:	4-08-PCSulfite2p8Crop.jpg 
Views:	70 
Size:	127.5 KB 
ID:	43619

    These images are darkish because I set the white-point as high as possible in the scanner, to clip as little data to white as possible (i.e., maximize the dynamic range). The black-point was set to the left side of the histogram (which was always the same). Gamma was 1.5.
    This is part of my camera-collection, lit by the overhead tungsten candelabra. It's hard lighting, which creates plenty of specular reflections to see how the dense part of negatives are doing. Unfortunately, my Coolscan IV ED scanner doesn't have enough dynamic range to cover such specular reflections well (and still show shadow-detail in the neg's), so many reflections clip to white.

    In the crops above, PC-Sulfite appears to have slightly less grain than XTOL. That's not true. In 22X loupes, they seem to have the same grain. The scanner's focus has a little variation, and the film isn't held perfectly flat, so grain is defocussed by unpredictable amounts. To get sharp images of grain, I want to photograph negatives in a microscope.
    Between these images, the XTOL negative clearly has more contrast and accutance than your PC-Sulfite. You can't judge a developer by comparing things like this.

  6. #26
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    Quote Originally Posted by Photo Engineer View Post
    I've stated before that stability in alkali goes up in the series Phenidone, Dimezone, and Dimezone S. The last word is that Dimezone S was the preferred agent and all new Kodak formulas would have used it. All Kodak instant films used it. Dimezone S is about the same in activity as the others. It appears to be less active, but that is partly due to the molecular weight compared to Phenidone.

    I think that some scanned examples of films produced by this developer compared to Xtol would be useful.

    PE
    Thanks for the comparison scans that Photo Engineer requested!

  7. #27
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    I'm glad to see that people continue to try things out -- experimentation is fun, IMHO.

    Also -- is that a row of Konica RF cameras up there? Pretty impressive!

  8. #28

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    Responding to several posts at once...

    Quote Originally Posted by dynachrome View Post
    I don't know what the advantage of this developer is.
    It's easy to mix (assuming you've pre-dissolved phenidone in something), and its grain is as fine as XTOL's. PC-TEA is more convenient and stable, but it has coarser grain. But this developer has the severe disadvantage of short shelf-life, so its appeal is the wonder that something so simple could produce great image-quality. XTOL is more practical because it lasts for 6 months or more.

    Quote Originally Posted by Trask View Post
    Also -- is that a row of Konica RF cameras up there? Pretty impressive!
    Gotta love those classic Konica RF cameras. Top quality, solid build, great optics, and a practical front film-advance. I wish that their front-advance had won in the market instead of the clumsier top-right advance-lever.

    Quote Originally Posted by Ryuji View Post
    It's not new.
    I'd like to give credit to where credit is due, so please provide a link or specific reference to an independent report of this formula.

    Quote Originally Posted by Ryuji View Post
    I don't know why you didn't see me saying it.
    Sorry, I didn't see where you said it in this thread (even upon re-read), and I missed your statement about it in some other thread. I'm sure you will provide a link to where you said you were aware of this formula.

    Mark Overton

  9. #29

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    Mark I think it would be better and more practical if you make test strings of at least 3 exposures, box speed, minus 1 and plus one.

    I'm lucky to have a hiQ camera body a Canon EOS 50e that let me do that automatically, makes test pictures from specific objetc, with sun (light here at this time of year, close to the polkar regions) against sun sidelighted open areas etc etc, I quickly burn a film with 5 separate triplets with space in the middle and repeat the same 5 subjects, cut the film in half and can test two developers under identical conditions.

    I secured 4 films like that within 15 minutes just before Christmas, and still have films to go.

    Doing it like that you test film-exposure-developer easier, and contrary to whats been said here, what interest us are PICTURES, not density curves, this is for practical experimenteres as far as I'm concerned, we are neither concerned with overly long storage capacities nor with hard to get chemicals....

  10. #30

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    Quote Originally Posted by analog what is that? View Post
    Mark I think it would be better and more practical if you make test strings of at least 3 exposures, box speed, minus 1 and plus one.
    Well, before that, the contrast needs to be matched.

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