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  1. #11

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    Isn't this the same as the sticky thread "Factor for enlarger head height adjustment" at the top of this forum?
    Richard

  2. #12
    ChristopherCoy's Avatar
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    Quote Originally Posted by youngrichard View Post
    Isn't this the same as the sticky thread "Factor for enlarger head height adjustment" at the top of this forum?
    Richard


    Probably - I'm on a roll with erroneous threads today. But then, if everything has been posted previously, whats left for us to discuss? Shall we all log out?

  3. #13
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    Christopher:

    Here are some suggestions:

    1) Cut one or two sheets of your 16x20 paper into four 8x10s;

    2) Work with them to get another good 8 x 10 print, using at least f/11 and possibly f/16 on your enlarger lens. Record the time you use for the resulting best print, and note an area on the print that is a highlight area with detail - that is the area you will attempt to match in your 16 x 20;

    3) Set up your enlarger (Beseler's site indicates the Printmaker 35 "can produce prints up to 11″ x 14″ on the baseboard or much larger when reversing the column and projecting on the floor") for the 16 x 20 size you want to print;

    4) Position an 8 x 10 easel so that it includes the highlight area that you are attempting to match;

    5) Open the lens two stops from the stop you most recently used for your smaller "reference" print. Use your test strip method to match the highlight using a #4 filter - the exposure time should be close to the time you used for your 8 x 10 reference print;

    6) When you determine the correct exposure time for the highlights, do a test on another 8 x 10 section of the image that shows how the shadows will appear with the new #4 filter. If they look good use that filter. If they are too light, increase the filter number and recheck both highlights and shadows. If they are too dark, decrease the filter number and recheck both highlights and shadows;

    7) Once you have both the shadows and highlights looking good in 8 x 10 sections that you have tested, move your attention to the mid-tones. Depending on the image, you may find that slight adjustments to the mid-tones may have the greatest effect on the results;

    8) When you are happy with the smaller 8 x 10 excerpts for highlights, shadows and mid-tones, you can try a full 16 x 20, to see if the "whole" is different from "the sum of its parts";

    9) Note that it is important to do the tests on the 16 x 20 paper (cut into smaller pieces) rather than paper that started out 8 x 10. Otherwise you may run into problems arising from differences in the emulsions.

    Finally, I would suggest avoiding exposures as short as 3 seconds. They are hard to repeat, and give no reasonable opportunity for dodging and burning.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  4. #14
    ChristopherCoy's Avatar
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    Quote Originally Posted by MattKing View Post
    Finally, I would suggest avoiding exposures as short as 3 seconds. They are hard to repeat, and give no reasonable opportunity for dodging and burning.

    I knew the negative was underexposed when I contact printed the proof sheet at 5 seconds. I set the negative up and used a 5x7 for a test strip. I figured the shorter the exposure the less gray it would be. After a few test prints at 2 seconds, I had an image, but it was light. The true blacks in the image were gray. So I added a #2 filter and ran it for 2 seconds. The darks were slightly better but it was still to light. So I went up a step to the #3 filter at 2 seconds, again slightly better but the darks were still to light. So I went up to 3 seconds still with the #3 filter and the 8x10 came out to my liking. I'm sure that it isn't correct or proper, but it produced something that I was able to mat and give to a friend as a reminder of our old stomping grounds. It is by far gallery ready, but it worked. The short exposure left enough white, and the filter made the blacks dark enough. But this is how I learn things.

    And, we wont even talk about dodging and burning yet. As I said earlier I'm just happy to get an image from the camera to the paper. Right now I'm concentrating on trying to get images with good shadows, highlights, and mid tones. Once I feel like I have gotten that down good enough, I'll venture into the little things like dodging and burning, and tweaking prints to perfection.


    But I definitely appreciate all the information you posted above! It's definitely a good reference for me.

  5. #15
    MattKing's Avatar
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    Christopher:

    There is nothing wrong with a three second exposure at f/5.6, it is just more difficult/awkward/inconvenient/less flexible to work with than a twelve second exposure at f/11.

    And I for one would hate to have you lose interest in what you are doing because of anything that is more difficult/awkward/inconvenient/less flexible to work with than it need be.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  6. #16
    ChristopherCoy's Avatar
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    Quote Originally Posted by MattKing View Post
    And I for one would hate to have you lose interest in what you are doing because of anything that is more difficult/awkward/inconvenient/less flexible to work with than it need be.

    Trust me, I don't know that there is anything that can make me loose interest now that I've returned to the dark room. It is every bit as exciting as I remember it being in high school. Maybe even more so now because I actually care, and comprehend what I'm learning and doing.

    But, that's how I learn. I never thought of raising the aperture on the enlarging lens to increase the exposure time, to allow for some dodging and burning, until you just mentioned it. And now that you did, that's opened up an entire other thought process on how to make that print better. hmmmmm...... I may have to wet some trays tonight after work.

    I never think of adjusting the aperture on the enlarger, because not once can I ever remember changing the one in class. And I constantly think about the exposure triangle when I'm shooting, I don't know why I don't think about it in the darkroom.....
    Last edited by ChristopherCoy; 10-31-2011 at 04:44 PM. Click to view previous post history.

  7. #17
    RalphLambrecht's Avatar
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    Quote Originally Posted by Steve Smith View Post
    Not sure about the best, certainly the most used!


    Steve.
    same here
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  8. #18
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    Quote Originally Posted by Doremus Scudder View Post
    Only 3 5x7 sheets, and 3 8x10 sheets to get one 8x10 right? Seems like a lot less paper than I use getting to a final print! After test strips, it's usually 4 or 5 sheets just to get close, then starts the fine adjustments.

    That said, since you have the dodging and burning and contrast already "in the ballpark," you should not have to make too many 16y20s to get where you want.

    However you need to use your enlarger to get a 16x20, the head will be farther from the baseboard and the enlarging exposure appropriately more (inverse square law ... can't break it!)
    there is more to iy than that. you also need to account for the belloes exrtension of the enlarging lens

    Use the 4x enlargment factor as a starting point, keeping in mind that larger prints often need a bit different contrast (you may want to tweak that a bit). Think of your dodging and burning as percentages of the total exposure and scale them up to fit your new print size (you may want to tweak them a bit too)[/QUOTE]might as well record them as f/stops ang get used to f/stop timing!.

    Don't be afraid to use some paper to get a print you are happy with! The best tool in your darkroom is the trash can!

    Best,[/QUOTE]
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  9. #19
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    The inverse square rule applies to enlargement the same way it does to studio lighting - double the distance, lose a stop, halve the distance, gain a stop. So going up to a 16x20 from an 8x10 is roughly 4x the distance, or two stops. If your base exposure is 3 seconds at f5.6, then give it 12 seconds as a starting point on your test strip (still do test strips!). you'll probably want to go up at least one grade in filtration, maybe a grade and a half. So you'll have to add another half to whole stop for the filter grade increase too. Try starting at grade 4, 24 seconds, and give your test strips three exposures at 12, 24, 36 and 48 seconds to see where the truth lies.

  10. #20
    Steve Smith's Avatar
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    Quote Originally Posted by TheFlyingCamera View Post
    The inverse square rule applies to enlargement the same way it does to studio lighting - double the distance
    Double the distance loses two stops as the light is now illuminating four times the original area.

    The clue is in the title: Inverse Square Rule!


    Steve.

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