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  1. #11
    trexx's Avatar
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    The lamp house should have a lever with three positions. Filtered Hi, Filtered Low and White light. Can you see the filtration change as you change contrast? This may be stuck in white light position.
    D-76 is a standard developer, although not one I use.
    Ansel Adams - The Negative

  2. #12

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    I agree that this is wrong. I use the same paper and I think I have 150w bulb. I usually get around 15s at f5.6 or f8 (I could check my notes, but one of the two) for 10 x 8"-ish enlargements.


    Have you got one of those (e.g. Schneider Componon S) lenses with a lever that overrides (opens up) the aperture setting whilst focusing? i.e. Could you be printing at f2.8 or 4 without knowing it? As mentioned the bulb wattage if the other thing to check.


    You shouldn't need to shut down to f11 or beyond so something needs fixing. Of course, ND filters would work but I kind of feel that that would be a bodge instead of understanding the cause.

  3. #13

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    Thanks, everyone, for your help.

    Okay - I checked the Saunders / LPL D6700 enlarger that I have.

    There are no attenuators on this enlarger.

    And the lamphouse doesn't have those three position you mention, Trexx.

    I had a closer look at the enlarging lens I have - it's a 90mm Roganar-S (I'm waiting to pick up a 6-element lens, but it'll do in a pinch). It stops down from f4 to f22 without a problem.

    The thing is, when I compared it to the only other enlarging lens I have (a el-nikkor 50mm), it seemed as if the aperture curtain is off by about a stop. That is, what is f8 on the el-nikkor looks to be a little over f11 on the Rodagon when I eyeball the two curtains. Can two lenses of different lengths be compared this way?

    I don't know if a stop difference will be the solution here - but I can't see anything else on the enlarger that would indicate anything else. The lamp is an 85W. It's housed properly. The condenser screen is in place.

    It'll be the weekend before I can get back into the darkroom to experiment - but it's a real puzzler for me.

    Thanks again for everyone's help.

  4. #14

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    Correction - I just had a closer look at the two lenses and the Rodagon curtain seems to be off by two stops. So, I guess, my question is, should two lenses of different lengths have the same looking aperture curtain when I look down the front of each lens?

  5. #15
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    Doesn't your lens have at least one more f stop you can use on it? It's just like a camera; stop down if there is to much exposure in the desired exposure time. With most medium format enlarger lenses, f/11 is two or three stops from wide open. You can easily go a few stops farther without sacrificing quality, especially in the small enlargements you are doing. It is also possible that your negs are thin.
    Last edited by 2F/2F; 08-02-2011 at 09:14 PM. Click to view previous post history.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

    - Rob Tyner (1944 - 1991)

  6. #16
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    Quote Originally Posted by Henry Yorke View Post
    ...should two lenses of different lengths have the same looking aperture curtain when I look down the front of each lens?
    No way! The "f" in an f number stands for "focal length," and the slash indicates division, with the result being the effective aperture diameter. With that info, you can figure out the rest: two different focal lengths divided by the same number equal two different effective aperture diameters. The aperture corresponding to f/11 on one FL lens is not the same size as the aperture corresponding to f/11 on another FL.

    I would check out a basic photo text from the library. It will explain the basics of f stops. "Photography" by London and Upton is a good standard to check out. It will also give you a guide on how to judge the exposure and development of your negatives, and how to troubleshoot printing problems like the one you are having. They are also common in used book stores and thrift shops, usually for very cheap. Any edition is fine. (Some editions are by Upton and Upton, not London and Upton. I believe they were married at one point, and then not, or vice versa.)
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

    - Rob Tyner (1944 - 1991)

  7. #17

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    Sigh - there's my ignorance carrying me only so far again.

    Thanks for the note and the book suggestion, 2F/2F.

    Just casting about for a solution to this problem.

    Thanks again for all of the help.

  8. #18
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    If you want the best quality then sto down the lens for 2 stops. So a 5.6 lens it's working range is F11 for best quality. (leave it there..)

    Second you must optimize you negative for best print quality (range of gray levels). Someone mentioned 15 secs. This is possible, but could also be the cause of a denser negative. What works for him, is not sure it will work for you...

    At last a print time comes out of all your variables. Maybe i would use lightbulb replacement with a lower value or take a longer lens so the distance is longer between lens and paper (increase time). A second benefit is that when using a longer lens, you use lens part of the lens glass (only the middle part) so the sharpness will increase a little bit.

    I assume you want longer times to work on your image (burn)

  9. #19
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    Quote Originally Posted by Henry Yorke View Post
    Sigh - there's my ignorance carrying me only so far again.

    Thanks for the note and the book suggestion, 2F/2F.

    Just casting about for a solution to this problem.

    Thanks again for all of the help.
    I wouldn't be down on yourself about it! There is nothing wrong with ignorance; the word carries a bad connotation, but IMO it is not a bad thing in and of itself. One does not learn much without it, the way I see it. I would guess that most photographers learn from other photographers correcting their mistakes more than they learn from books. I certainly did. But a book is a good starting place to be exposed to some basics if you cannot get into some sort of local class.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

    - Rob Tyner (1944 - 1991)

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