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  1. #31
    Mainecoonmaniac's Avatar
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    Very observant!

    Quote Originally Posted by Michael R 1974 View Post
    EDIT: I should add since you're using x-ray film, film speed and contrast could be all over the place under tungsten or daylight conditions etc. If you're doing your step wedge tests with tugsten light for example, I'd expect very poor speed.
    The film is GREEN sensitive. Tungsten light is reddish which the film is not very sensitive to. I think the film speed test should be done in daylight with a neutral colored subject.
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
    Aaron Chang

  2. #32

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    Thank you MR74. Although at 2 and 5 G respectively of Elon and HQ, it's hard to imagine the HQ playing only a minor supporting role to the elon. Recalling a book I have here "This Is Photography", Doubleday,1963, Miller and Brummitt of EK, an experiment is carried out with DK60a with Elon removed, then with HQ removed, and the results were quite varied. I say this to note that Elon and HQ are more-or-less equally reactive by weight, in that there are 2.5 G apiece per liter in the DK60a formula.
    Wile none of this is pertinent to today's experimenting, it does go to show that they don't have lopsided characteristics by weight. This is what has me leaning toward buying a bottle of metol for the sulfite I have here, and going with a D-23 derivative to fight contrast. As far as shadow detail in the "more pragmatic" approach which I had also already decided to undertake, I'm not getting any shadow detail till I get down to at least ASA 40, and I think 32 and 25 would be more like what I'm looking for. Since all these other guys are getting ASA 80 and up, I can see that my ASA 32 is going to cause dens highlight problems, hence my interest in pyro or a weak D-23. For now I'm avoiding the pyro because I have a habit of keeping my fingers in the soup the whole time. Thanks, guys.

  3. #33

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    When comparing the types and concentrations of developing agent(s) in developers, it is critical to look at the operating pH (ie alkalinity) of each of the formulas. Different developing agents become active at different pH levels. Metol, for example, can develop film at an essentially neutral pH (~7 - as in the case of D-25) albeit with long development times. Other agents such as Hydroquionone, Catechol and and p-Aminophenol need significantly higher alkalinity to function as primary developing agents. You can't compare the function of Hydroquinone in D-76 to its function in DK-60a which contains a stronger alkali, and much more of it.

    Bottom line, you can't compare developers by looking only at the developing agents and their concentrations. The other parts of any scientifically balanced developer formula are just as important, if not more important in determining how the developing agents will work, and in determining the working characteristics of the developer. Therefore it is incorrect to characterize a developer as low or high contrast merely based on whether it contains Metol or Metol and Hydroquionone. D-23 was designed to work very similarly to D-76. That said, there is nothing stopping you from trying dilute D-23. Maybe it will help, maybe it won't. Worth a test.

    With respect to Pyro, personally I'd suggest either a specialized low contrast developer, or a compensating developer such as FX-2 before going to Pyro, particularly if you are looking for higher film speed than you are getting from D-76. While certain superadditive formulations such as Pyrocat are said to give full film speed (like D-76), most general purpose Pyro/Catechol staining developers do not, nor are they inherently low contrast developers. There are, however, some highly dilute Catechol developers formulated for very low contrast. Maybe those would be worth a try. If you want to try Pyrocat, what you may want to try is some sort of stand or semi-stand technique. While this can be disastrous with many staining developers, it is said to work with Pyrocat, and may result in decreased contrast with half decent film speed.

    In the end, you're using a high contrast film. It isn't easy to tame the contrast without losing film speed. Who knows, maybe your EI 25 is all you're going to get. How do we know all these other people are getting EI 80 and higher? Under what conditions? Do they have good shadow detail? Etc.

  4. #34

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    Hmm... never heard of FX2. Looks complicated. Although thoughts of Acufine and Acu-1 spring to mind. I'm too lazy to experiment with divided-bath developers.

  5. #35

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    I'd always suggest trying simple things first. So perhaps run your experiments with dilute D-23. If it doesn't work, move on to something else. Divided development can also help reduce contrast somewhat - and you can do it with D-23 if you want to include that in your D-23 experiments. There are several paths to try if you want lower contrast from a high contrast film.

  6. #36

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    Pardon for my bringing this thread up before the eyes of the disinterested. OK, today's experiment in shooting the side of my log house in the late afternoon after some tree shadowing had already set in because of the early autumn sun. Not the optimal conditions, but I squeezed it in anyway. A 12 inch uncoated in a Betax #4 set at 1/5 tested as accurate, and about f/24. Film speed on a known-accurate Luna Pro was rated at ASA 20 with a K2 filter on the lens. Film developed 6 minutes, 70-72 degrees in D-76 1 :3. Henceforth, a K2 will be a permanent installation for this Fuji HRT. When using ortho film, a K2 is the only hope in correcting to anywhere near pan film with a K2.
    The results: Still a bit underexposed. Unbelievable. How slow is this stuff? Shadow detail is definitely a battle to achieve. Next trial--ASA 16, same development. That should about get it pegged. But not a bit of forgiveness on underexposure, because shadow detail with this film is at a precious premium.

  7. #37
    Bill Burk's Avatar
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    When using ortho film, a K2 is almost like using a safelight. I would expect it to have a much higher filter factor than it would have for Pan film.

  8. #38

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    Quote Originally Posted by Bill Burk View Post
    When using ortho film, a K2 is almost like using a safelight. I would expect it to have a much higher filter factor than it would have for Pan film.
    Good to hear from you Bill. Thanks. I had also known this before making the decision. BTW-The tentative new ASA 12 I've chosen has the filter factor included. But since my shots will more often be landscape type scenes, it's necessary for getting clouds to show in the sky. I refuse to shoot color-blind scenes with no sky. But it is surely the only trick in the camera bag to get ortho film to correct.

  9. #39

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    I've reconsidered an earlier idea I had tossed out concerning permanent filtration. I say permanent because this film would be useless for landscape without it, for the sake of sky and clouds. I'm going to move over to a mis-marked 62mm X1. As we know, X1 is a designation for a #58 green, which is quite green. Not cyanny, not yellowish, either one. A very neutral PMS green. The filter I have is more yellow-green (see Pantone 368), yet marked as X1 and not the No. 11 I believe it really is. The problem with the #8 K2 is that it seems to kill off any hope of shadow detail, shadows being blue in hue. I will perform one more experiment at ASA 16, yellow-green factored in, and continue same development. Green x-ray film is tough-stuff. But I really do believe it is workable for landscape and outdoor work.
    http://www.google.com/imgres?imgurl=...9QEwAQ&dur=679

  10. #40
    Bill Burk's Avatar
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    I'm not suggesting that you can't use K2... Just that the filter factor might be surprising.

    An idea that may work for you... Look up "Hutching Filter Factors" for a technique (not specific factors in your case) of light reading shadows through the filter, placing on shadow Zones, then applying a filter factor.

    So work out the factors needed to get shadow detail. That's where you usually lose out (for instance with a red filter and normal pan film, blue shadows and red filter often combine to lead to unprintable negatives because of the double-whammy).

    You say you'd refuse to have blank skies, but I allow for exceptions because there are plenty of landscape compositions that work fine without clouds.

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