Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,338   Posts: 1,537,696   Online: 844
      
Page 1 of 4 1234 LastLast
Results 1 to 10 of 34
  1. #1
    David Lyga's Avatar
    Join Date
    Nov 2007
    Location
    Philadelphia, PA USA
    Shooter
    35mm
    Posts
    1,236

    IN CONQUEST OF CONTRAST

    Ever since I developed my first roll of film, (size 127) when I was 14 (1964), I have pondered, with little lasting success, about 'determining to finality' the correct amount of contrast that a negative should hold. Roll film obviates the luxury that Ansel Adams had, namely being able to effectively gain the proper contrast on a subject by subject basis. Literature at the time spoke of an ideal gamma (ie, like contrast index) of about .7 or .8. I wondered, and still wonder, why 'proper' gamma cannot be 1, the same tonal displacement/rendition as seen by the naked eye.

    I have toyed with 'liking' more contrasty negatives and then have reverted to more subdued indices but have never actually reached a conclusion. There is 'something' uplifting about a 'gutsy' negative that is a little underexposed. But there is also 'something' about a negative that 'gets it all' (shadow detail in abundance with highlights that do not appear opaque) and carries with it the 'safety' of being able to render the final image with more flexibility. But, with this flat abundance of full detail, the mid tones do suffer from lack of differentiation. I have wondered if a more contrasty negative, with gorgeous mid tone separation, is really the 'ideal' and its semi-lack of shadow detail (to prevent the highlights from burning in too much) might provide the truest aesthetic rendition (ie, 'less is more'). By allowing deepest shadows to appear nonexistent perhaps we now are allowed to 'read into' the morass of darkness and come up with a more 'poetic' rendition. I really do not know but it would be interesting to hear what the intelligentsia amongst us would impart about this dilemma of sorts. - David Lyga
    Last edited by David Lyga; 11-28-2011 at 08:13 AM. Click to view previous post history.

  2. #2
    Thomas Bertilsson's Avatar
    Join Date
    Jan 2003
    Location
    Minnesota
    Shooter
    Multi Format
    Posts
    14,253
    Images
    297
    Your paper and paper developer have characteristics that you should match with your negatives to eke the maximum out of your materials.
    It's possible that a negative with a contrast index of 1 is completely beyond the range of your paper.
    But art is subjective, so you judge for yourself what's best for your pictures. You might find something interesting at a high gamma. Nobody else can tell you what to like.
    "Often moments come looking for us". - Robert Frank

    "Make good art!" - Neil Gaiman

    "...the heart and mind are the true lens of the camera". - Yousuf Karsh

  3. #3
    Bill Burk's Avatar
    Join Date
    Feb 2010
    Shooter
    4x5 Format
    Posts
    3,230
    Images
    46
    Thomas is right, it is the paper that dictates a slightly lower contrast index than 1.

    In Post 38 of Zone Placement, Stephen Benskin gave us a chart that pairs Subject Brightness Range and Paper Log Exposure Range. http://www.apug.org/forums/viewpost.php?p=1233813

    ---

    This will tell you what your Contrast Index should be. Used as a point of departure, you will be able to hone in on what you are looking for.

  4. #4

    Join Date
    Aug 2005
    Location
    Los Alamos, NM
    Shooter
    Multi Format
    Posts
    2,052
    Most manufacturers recommend developing film to a gamma of about 0.65 to 0.7, which matches most papers on the market. The recommended development times are geared to this contrast, but different agitation routines can shift it a quite a bit.

  5. #5

    Join Date
    Feb 2010
    Location
    Montreal, Canada
    Shooter
    Multi Format
    Posts
    4,641
    David, most of what your talking about in your second paragraph has to do with subjective, aesthetic preferences. Exposure and development of the negative should be tailored to the original scene and how you visualize the final print.

    However since you are using 35mm it is worthwhile to keep a few other image characteristic factors in mind, in addition to overall contrast and paper curves. For one thing, targetting a contrast index of 1 will result in significantly more grain in the negative. Along with this goes reduced sharpness. It will also raise micro contrast. These are relatively minor concerns with large format, but are material considerations when enlarging small negatives. Although again, in the end it depends on what you want things to look like, as Thomas points out. I'm just trying to put all the variables on the table.

  6. #6
    Nicole's Avatar
    Join Date
    Sep 2004
    Shooter
    Multi Format
    Posts
    2,548
    Images
    8
    David, I agree with Thomas... art is subjective. I try not to get caught up in technical correctness and instead use a poetic approach, allowing each negative to determine it's own most suitable level of contrast, best judged by vision and emotion.

  7. #7
    jp498's Avatar
    Join Date
    Oct 2009
    Location
    Owls Head ME
    Shooter
    Multi Format
    Posts
    1,467
    Images
    74
    If I shoot a whole roll under a certain lighting condition, I will write that on the roll and choose a developer suited to the results I want. If it's a roll of mixed images, I will use a normal-to-me developer. I want a neutral/average contrast on the negative, and have the flexibility to print it with more or less contrast. I have PMK and caffenol-c for normal and reduced negative contrast, pyrocat-HD and xtol for normal contrast, and hc110 or pushing one of the other developers for increased contrast.

  8. #8

    Join Date
    Feb 2005
    Location
    Richmond, VA
    Shooter
    Multi Format
    Posts
    1,066
    As Bill and Thomas say, the paper's range has long been known to be the limitation of the process. But I have spent considerable time (and still do) thinking about the question raised here - how much range should be in the neg and how the selection of the paper grade (or filter used) influences the intermediate value separation after the opposite ends of the tonal range is achieved in the print.
    Fred Picker once said that for 35mm, a slightly flat neg was good, the print benefiting in "look" from a slightly higher contrast in the printing.
    Many years ago, when I was teaching photography at a university, some students and I tried producing a set of negs with different contrast ranges of the same subject (4x5, tripod, etc) and printed them all on different contrast grades of the same paper to achieve the same end values. The negs that had the most range, printing on grade 1 paper had a boring flatness to them, although the highlights and shadow values were good. In fact, both the shadows and highlights had little local separation. This was in the 70's, at a time when VC papers were considered inferior, so split contrast printing was not an option.
    I still try varying the contrast of negs, using split printing to control contrast, and am still not finding what I would call a perfect neg range, except that something that prints well on grade 2 is probably a good default (now there's a surprise), allowing for artistic interpretation in different directions.
    I think it also depends on the film and developer characteristics - I just tried a roll of HP5, (most of this testing lately has been 120 roll film) with a test development with HC110, which came out a bit flat (I'd say -1). It included some sky areas, with clouds, shot with a yellow filter. When split printing, I found the base highlight exposure using Ilford filters, MGIV, and an Aristo V54 with #0 (#00 is too flat for the sky and cloud separation). Finding the low end with #5 locked in blacks, but didn't lower the lower midtones enough for the interpretation I was after, so I started working my way through the contrast range for the second (high contrast) exposure, settling on #4. But it occurred to me that I was moving values that are also influenced by the mid tone separation in the negative. The print looks great, and I wondered if I'm worrying too much about the neg, beyond just being sure everything is there, with reasonable contrast.
    I'm not comfortable with this thinking, as my entire experience has been driven by achieving the fullest range negs I can. Since discovering APUG, I have tried many things I had not considered before, and am now trying to settle on a couple of films to use going forward, which might be Delta 400 and FP4. I'm trying HP5 since I got some free rolls with paper (and, unfortunately, Delta 400 doesn't come in 4x5). So, this is on my mind lately - sorry for the long winded post.

  9. #9

    Join Date
    Aug 2010
    Location
    Germany
    Shooter
    Multi Format
    Posts
    658
    Images
    15
    David, when in doubt., do contact prints.
    Many answers are hidden in there.
    Back in the days we've had those small Photax contact printers, with lamp and safe light stuffed in it..
    For roll film its a blast.

  10. #10
    ic-racer's Avatar
    Join Date
    Feb 2007
    Location
    Midwest USA
    Shooter
    Multi Format
    Posts
    6,195
    Quote Originally Posted by David Lyga View Post
    Roll film obviates the luxury that Ansel Adams had, namely being able to effectively gain the proper contrast on a subject by subject basis
    Multigrade paper brought that back.

    Literature at the time spoke of an ideal gamma (ie, like contrast index) of about .7 or .8. I wondered, and still wonder, why 'proper' gamma cannot be 1, the same tonal displacement/rendition as seen by the naked eye.
    Back on the days of Jones' experiments, many of the films were developed to high gammas. However, I'd say these are the
    reasons why you'd want your rollfilm negative to have less contrast than the scene

    1) Less development = less grain
    2) Less contrast in the negative = less flare during enlargements
    3) ("chicken and the egg argument") current enlarging papers are centered around a negative contrast 0.8 to 0.6

    Personally I'd not fry any negatives in the developer, and I'd use hight contrast paper or paper developer to get the effects you want in the prints. That way, one can still print a less-contrasty tonal scale in the future.

Page 1 of 4 1234 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin