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  1. #1
    Rudeofus's Avatar
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    Results from Mark Overton's recipe

    Mark Overton recommended a B&W developer recipe which I tried on Kodak Tri-X 400. Since his recipe hit me by surprise while I already had a finished roll of TriX 400 (exposed at ISO 1600) sitting on my desk I used this roll to test his recipe. A few things in my setup deviated from Mark Overton's recipe:

    • I mixed the metaborate from lye and borax, using stoicheometry to determine the correct composition.
    • Since I misjudged the degree of hydration of the metaborate in Mark Overton's recipe I effectively had only 3/4 of the suggested metaborate content in my mix
    • Since my film roll was exposed at ISO 1600, I developed for 12 minutes instead of Mark's recommendation of 8 minutes


    The two attached images show tiny crops of two images. Image 1 is from TriX 400 exposed at ISO400 and developed in Kodak HC110. Image 2 is TriX 400 exposed at ISO 16000 and developed with Mark's soup.

    Here is how I created these images:
    • Put negative in enlarger
    • Set enlarger to maximum enlargement, yielding a whole image area of 37.5x57cm, this is a factor of about 16
    • Careful focusing with grain loupe
    • Expose a 10x15cm sheet of photographic paper, develop/stop/fix/wash/yaddayadda
    • Scan photo at 1200 dpi (one pixel is about 21Ám on paper which is 1.3Ám on film)
    • crop image to satisfy APUG limits (650x650), no resizing!


    Since these are completely different motives there is no point in discussing tonality or characteristic curve (I will come to that some time later). The difference in grain, however, is quite visible.

    Happy discussion!
    Attached Thumbnails Attached Thumbnails TriX_ISO400_HC110.jpg   TriX_ISO1600_MO.jpg  
    Trying to be the best of whatever I am, even if what I am is no good.

  2. #2

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    Hi Rudeofus: I have a few starting point suggestions for evaluating the relative granularity of two developers, as I've done a fair bit of this sort of thing.

    1. The film should be exposed at the same EI to start

    2. I suggest taking the subject matter out of the equation - ie expose a uniform, out of focus test card at various exposure values

    3. The films must be developed to the same contrast in both developers

    4. Start by evaluating a middle-tone density. Choose matching (or as close as possible) densities from either roll

    5. Enlarge the two chosen frames/sheets exactly the same way onto enlarging paper

    This is an attempt to evaluate the relative graininess (and characteristics of the grain) of a given type of film, developed in two different developers such that in real life they would both print very similarly in terms of exposure time and contrast. This way you could conclude, for example, that for a given silver density in the negative, intended to produce the same tone in a print (say zone VI), one developer (at a given dilution) produces a grainier or less grainy negative density than another.

    I think this is worth considering, as there have been several threads going recently regarding home brew formulas versus XTOL etc, in which people are talking about relative graininess without any sort of methodology.

    In your case here, you're comparing a normally developed film in one developer, to a film pushed two stops in a different developer. We can't draw any meaningful conclusions from such a test.

    Hope this helps.

  3. #3
    Rudeofus's Avatar
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    Michael, I am fully aware that my comparison is not a comparison of equals and should not be considered scientific. I posted the details under which both shots were made to make that clear to anyone. Next in line will be a series of the same shot taken 36 times to fill a roll and then cut and developed with different soups. As soon as this has taken place folks will show up and inform me that I'm not done yet because I need to investigate 20 different films, various push and pull levels and go through a host of other possible influences.

    Let me be very clear about this: I won't.

    I posted this to show everyone that MO's recipe, while working nicely is not a miracle recipe. I got pictures which I am happy with and I learned a lot from mixing a dev myself. I will continue trying home brew recipes because it's fun to do and because I hope I will learn more about this subject during the next few years. My thread is here to encourage more people to try home brewing without fear that they will have to suffer through 2 years of unusable images. It will be a long time before I get anything close to Xtol if I ever get there, so what, I enjoy doing it.

    PS: This is the whole print from TriX@1600 souped&pushed in Mark's recipe.
    Attached Thumbnails Attached Thumbnails TheBridge.jpg  
    Trying to be the best of whatever I am, even if what I am is no good.

  4. #4

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    Ok. Just thought it was worth mentioning in light of all the recent developer formulation threads. People are posting scanned images and, in some cases, trying to draw conclusions regarding speed, sharpness, graininess etc from the "evidence". Without meaningful comparisons, all we can say about any of these formulas is they are capable of developing a latent image. Not much more.

  5. #5

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    Quote Originally Posted by Michael R 1974 View Post
    Ok. Just thought it was worth mentioning in light of all the recent developer formulation threads. People are posting scanned images and, in some cases, trying to draw conclusions regarding speed, sharpness, graininess etc from the "evidence". Without meaningful comparisons, all we can say about any of these formulas is they are capable of developing a latent image. Not much more.
    Michael,
    I agree about the need to test films exposed at similar EI.
    However,I think that before being too critical one needs to take into account that the posting of scanned images for assessment of granularity is in its infancy.Furthur, I am not even sure if we are supposed to discuss the protocols here as some Photoshop is inevitably involved.So at this time there is no Protocol.

    If you want a Protocol and the present situation is not acceptable to you,what Protocol do you propose?

  6. #6

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    Quote Originally Posted by Rudeofus View Post
    Mark Overton recommended a B&W developer recipe which I tried on Kodak Tri-X 400.
    I should mention that the purpose of this developer is to give lower contrast and more latitude. Its shadow-grain is worse than XTOL. Highlight grain might be comparable if you're not pushing. A second purpose is to be a convenient concentrate. I'm not pursuing it now due to limited time, but I'm hoping that Rudeofus or somebody else can refine it and verify its robustness. Much of my shooting is contrasty (sun/shade, harsh indoor lights), so I intend to get back to this if others don't do so first.

    Regarding measuring grain: I think the best way is with an enlarger and scanning the print, as Rudeofus did. With my $1000 Nikon negative-scanner, grain looks different scan-to-scan due to focus-variation, unless I manually focus it at one spot I'm interested in. The scanner then provides a decent idea of relative graininess of two neg's, but it's not good enough to see individual grains. I hope to be able to get photographs from the microscopes at work, but I'll need to figure out a way to back-light the neg's.

    Rudeofus: Congratulations on successfully mixing your own developer. Now you're hooked!

    Mark Overton

  7. #7

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    Quote Originally Posted by Alan Johnson View Post
    Michael,
    I agree about the need to test films exposed at similar EI.
    However,I think that before being too critical one needs to take into account that the posting of scanned images for assessment of granularity is in its infancy.Furthur, I am not even sure if we are supposed to discuss the protocols here as some Photoshop is inevitably involved.So at this time there is no Protocol.

    If you want a Protocol and the present situation is not acceptable to you,what Protocol do you propose?
    Alan, I detailed it in my first reply to Rudeofus. Crank up the enlarger head and make relatively high magnification prints. The differences become plain to the eye, and you don't need to rely on high resolution scanning with all its artifacts. You can scan at screen resolution and clearly compare the prominence of grain.

  8. #8
    Rudeofus's Avatar
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    Quote Originally Posted by Alan Johnson View Post
    However,I think that before being too critical one needs to take into account that the posting of scanned images for assessment of granularity is in its infancy.Furthur, I am not even sure if we are supposed to discuss the protocols here as some Photoshop is inevitably involved.So at this time there is no Protocol.
    Alan, if you read my post carefully you'll see that scanning procedure and possible post processing from scanner software and format conversion had little influence on the outcome of my measurement. Michael calls for scans of highly enlarged photos which is exactly what I did. I have no idea what all this fuss is about, I sure hope these are not just copy&paste standard responses thrown at anyone who tries home brewing.

    Quote Originally Posted by albada View Post
    I should mention that the purpose of this developer is to give lower contrast and more latitude. Its shadow-grain is worse than XTOL.
    Let me say this: I have used quite a few films with a few developers in combination and this is the first time I could use a shot aimed at the sun directly and put it on paper without any dodging and burning. I don't like the grain in the sun rays much but I'll try to find out how to improve this. Hell yeah am I hooked one home brewing, thanks Mark!

    I would like to learn why this recipe did what it did. It looks very similar to PC glycol in composition but adds sulfite and uses more phenidone/ascorbate, two things which I would expect to cause higher contrast and small grain. Did you develop this formulation yourself or did you get it from somewhere else?

    PS: I will get the darkroom cookbook soon and will have access to at least one from Ryuji's list of books about photo chemistry, so I should learn about this subject matter shortly. The next practical experiment on my list is expose TriX @ 400 and try Mark's recipe as it was intended (with full metaborate content).
    Trying to be the best of whatever I am, even if what I am is no good.

  9. #9

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    Rudeofus,
    My comment was not directed at you.
    I'm just saying to Michael don't write off high resolution scanning as useless simply because nobody has evaluated its ability to distinguish different developers yet.
    It could be done on DPUG using say Perceptol, Xtol and Rodinal.
    It's probably not as good as the enlarging method but potentially useful if anyone makes a homebrew to test.
    It has not been evaluated yet.

  10. #10

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    Quote Originally Posted by Rudeofus View Post
    I would like to learn why this recipe did what it did. It looks very similar to PC glycol in composition but adds sulfite and uses more phenidone/ascorbate, two things which I would expect to cause higher contrast and small grain. Did you develop this formulation yourself or did you get it from somewhere else?
    For reference, the formula is here: http://www.apug.org/forums/viewpost.php?p=1285367

    This developer has a relatively low alkali/phenidone ratio. I suspect that this results in poor buffering compared to the activity of the phenidone, causing a high degree of compensation -- suppression of highlight development -- which reduces contrast. It also has a low ascorbic/phenidone ratio of only 18, whereas this is >= 40 for most PC developers. This ratio is 0 for ultra-low contrast POTA, so it makes sense that contrast will drop as the ascorbic/phenidone ratio drops. However, I suspect that poor buffering is mostly responsible for the low contrast.

    You could say that I invented this myself, but the truth is I encountered it by accident. I was trying to create a concentrate-version of PC-Sulfite, and not all of the ascorbic acid would dissolve in the propylene glycol. So I added some sodium metaborate to assist dissolution. That forced the sulfite-level to be much lower (35 vs 90 g/L) to keep pH=8.2. That loss of alkali in turn hurt buffering, which (I suspect) reduced contrast.

    If you want to reduce contrast even more, I suggest multiplying the quantities of all components except phenidone by a factor less than 1.0, and increasing dev-time. This will multiply both ratios by your factor, which I believe will increase compensation.

    BTW, have you tried Diafine? I've read that (1) it has good compensation because it's a divided developer, and (2) it pushes Tri-X well.

    Mark Overton

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