How To Analyze a Negative

Discussion in 'Enlarging' started by Christopher Walrath, Dec 9, 2009.

  1. Christopher Walrath

    Christopher Walrath Member

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    Well, I have been printing for close to a year now. And with some modicum of success, I am proud to report. I was leafing through the latest Photo Techniques magazine and came across an article by John Sexton: Contact Sheet - Seeing the Print Potential. I am reading and he talks about a starting point by examining the contact sheet and by looking at the negative on a light table to guage the contrast range in a negative.

    Now, for the totally newb question. How, exactly, the H-E-Double Hockey Sticks do I do that? What exactly am I looking for? I go off the contact prints presently and seem to be doing fine. I'm not looking for a miagic bullet here or anything. As I said, what I am doing seems to be working though my prints come out a bit flat and I need to work on them.

    What do you 'Master' (compared to me) printers do? What do you look for in your negs when you are planning a print session and how do you go about it? Just looking for ideas and I welcome any and all long winded answers. The more so the better.
     
  2. mike c

    mike c Subscriber

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    Sexton got 39 or more years on you Chris,give it time.
     
  3. jp80874

    jp80874 Subscriber

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    First I determine where I will hang the final print and what light is there. The same print looks better or worse in different light. In my darkroom I have hung a print that looks good over a wide range of tones in my target light. I compare my wet test strips to that print. I compare my proof and then final prints to that target print. Calculating roughly 10% for fiber dry down, I am looking for a final print that has that range of tones and is about 90% as dark/light as the target.

    I bracket my negatives and my final print is a 7x17 contact sheet. On the light table I look for detail in the shadows. The negative with the most detail is the one I will print. If I have too much light the negative will be too dark and the detail lost. If not enough exposure there will be little detail. I can't print what isn't there.

    If there is a wide range of light intensity I will see how bad/wide on the first contact sheet. I may print an area needing the most exposure determined with test strips or gut feeling, and then figure how much to dodge other areas. Or I may pick a middle light level and dodge or burn others to need.

    The test strip will also tell me what contrast to use. Another area may need more or less contrast than the overall. I will print accordingly with a second contrast filter, ie: a version of split grade printing. Add to that the vocabulary learned in sixty years of sailing and I am almost there.

    John Powers
     
  4. Mike Wilde

    Mike Wilde Member

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    A cheap way to determine contrast visually with a light table, and said negative under examination is a pair of cardboard cards with holes punched in them, and a stouffer step wedge. I suggest that a 120 sized 31 step one is nicest ($50 or so), but I started out using a 1/2" x 5" 21 step one that I got for free from a former graphics art printer who had tons of them idle after they went digital with prepress.

    You flop the test neg and step wedge near one another on the light table or otherwise improvised light source plate. Put the card hole over the area of interst on the neg, and then slide the hole in the second card along the step wedge until the light tone matches. A human eye is very good at comparing and matching grey tones that are not to far apart. Make note of the value of the area. Then look at another area, compare to match its tone, and note it's area number. On a 31 step wedge the steps are .1 apart; on a 21 step .15 apart.

    Say I have a neg of a landscape and am using a 31 step wedge to match tones. I look and see the thin area of the negative that I want to print as the first discernable shade away from total black, like the shadow under a bunch of cedar trees is matched by step, say 8. Then I look to the highlights other than the sky, say to a light toned rock that is not otherwise shaded, and comapre it- it is matched by the patch number 19.

    Then I look to the sky, and find a light cloud that I want to show as light grey. It reads as a match to say 22. I would then find the usual contrast filter for a density spread from the specification sheet of the paper I am planning to use.

    Lets say it's Ilford MGIV; oh where did that little piece of paper go after I openned the box/envelope? (mine is now taped to the wall beside the enlarger) Steps 19-8=11x.1 LogD per step=1.1, x100 for the ISO range of the paper needed , which I recall is about grade 2 or so. For over 20 years I never knew what the little tables Ilford put on that sheet had in them that could mean anything to me; now I do.

    So I slap a grade 2 filter or whatever into the lamp house, or otherwise set my filters for grade 2, and then do a test print to figure how much time to make the rock be almost white. Once I find that time, I call that my base time.

    For the clouds now figure the burn in time, added on top of the base time for just the sky area. In a .1 step step wedge, every three steps along is equal to a stop of light.
    So in this example say the rock was just grey after 15 seconds of printing time in the test print (at whatever aperture). The are three steps (22-19=3) to the clouds that we want to see some light grey tone out of also above the value of the rock. Well rocks were light grey after 15 seconds; the sky then needs a 'stop' more time, ie another 15 seconds.

    You can see how this leads to f/stop timing. Look up Ralph Lambrecht's approach to this; it is great once you strart to get your head around it.
     
  5. Vaughn

    Vaughn Member

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    Judging from the neg on a light table is easy -- it just took me a few years of making prints (20 or so) and then bang, no problem. My brain even reverses the tones for me.

    It does help that my negs are 8x10...

    Vaughn
     
  6. MattKing

    MattKing Subscriber

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    Chris:

    I'll address the "What exactly am I looking for?" part of your question.

    While you are learning, you need some example negatives.

    As you print a variety of negatives, you will come across some that are hard to print, and others that are easy to print. Make a note of those easy to print ones!

    Some of those easy to print negatives will be a bit low in contrast, some will be a bit high in contrast and some, like Goldilock's porridge, will be just right. :smile:

    Make note of a few examples of each type (preferably with a wide range of tones) and refer back to them regularly. You can compare the appearance of new negs to your reference negs - look for density of highlights, density of shadows, and appearance of midtones. Putting the reference negs side by side with the new negs on a light table works best - make sure you use a magnifier (a good loupe is ideal).

    The "ring-around" at this site may help as well:

    http://www.ephotozine.com/article/Assessing-negatives-4682

    By the way, you may find initially that you will have a tendency to concentrate on the highlights and shadows. As you get more experienced, you will realize that for most images the quality of the print will depend more on the appearance of the mid-tones. Unless the subject is one where either the shadows or the highlights are paramount, you will find that if you base the contrast of your main exposure on the mid-tones, your print is likely to be more successful. For that reason, it pays to work hardest on learning to evaluate the midtones on your negatives.

    Have fun.

    Matt
     
  7. Anscojohn

    Anscojohn Subscriber

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    Hi Chris,
    On the light table, look at the clear edges of the film. Then take your eye to the neg and look for areas of the same density. If you choose to print your neg for the minimum amount of time to achieve the max black of which your paper is capable, those neg areas (if there are any, will be the bottom of foundation tone of your print.
    Look then for the heaviest part of the neg. When you print that neg for min/time-max black through clear film, that should be the highest tone in the print.
    Now look at the contact sheet and see how those tones relate on the contact sheet. (Your contact sheet should have already been exposed for min/max black time.) If the tones "fall" where they should, you are good to go with your first exposure. If not, you must use contrast-grade changes (and new max/black time )to get those tones as close as you can. After that, , local controls, or developer manipulation to get the tones where you wish them to fall exactly on the paper.
    Other people go the opposite direction and find a time for the high tones; then resort to the changes and manipulations. The old lab rats (some who had been printing before glass plate negs were supplanted by this here new-fangled sheet film came in) with whom I worked back in the early 1960s taught me that was the way to go, by laying the foundation tone and "working up." Hope that makes sense.
     
  8. ic-racer

    ic-racer Member

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    A few additional tips to those already posted:

    A) Usual contrast gradient of fine-art negatives is around 0.8 to 0.6, what that means is that they will have less contrast than you saw in the scene. You will get this back when you print, but if your negatives look dull, thats probably normal. A vivid contrsty negative that looks like a nice inverse of what you originally saw may actually be a pain to print.

    B) In many years of looking at negatives on a light table (30+ years), the one thing that I cannot always know is over-exposure. Usually not a problem with modern films, but lately I used some narrow range films.

    C) How do you learn to know what is what?? Look back at the negative after you printed it. That is your feedback. If it was difficult to print then you now know what a negative that is difficult to print looks like. Etc. If it was easy to print then you now have an example of a negative that is easy to print.
     
  9. ic-racer

    ic-racer Member

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    I have an old Phil Davis book that shows a grid of negitves of the same scene with all permutations of over/under exposure and over/under development. That is good to see for a beginner. Subtlties are difficult to pick up on book reproductions of negatives, though.
     
  10. CPorter

    CPorter Member

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    If you can see the detail on the negative on a light table with a loupe where you wish it to be represented in the final print, then you at least know the possibilities for printing it. That in turn can be supported by the other main point of that article, which is making a low contrast work print that enables you to really see all that information that the negative can faithfully render.
     
  11. Christopher Walrath

    Christopher Walrath Member

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    Well, I have decided to take the responses and create a text file that I will eventually print out and keep close at hand for reference. This is what I basically take thus far.

    Print the negative with the most detail. If it is too light with almost no detail it will be very dark. If it is to thick then it will be washed out. YOU CAN’T PRINT WHAT ISN’T THERE.

    Use your contact sheet to determine a base contrast range and gauge your printing from there.

    Pay attention to the midtones for a great print where highlights or shadows are not the paramount desire.

    Max black will match the unexposed edges of the negative. Use this for comparison within the negative.

    In order. Evaluate the mid tones. Make the base exposure. Then on to overall contrast changes. Place the shadows next. Then work with the highlights. Then employ local controls (dodging and burning).

    Compare the print to the negative so you know what it is you have printed.


    Thank you for the advice. I hope to get more ideas to integrate into a new procedure.
     
  12. Craig Swensson

    Craig Swensson Member

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    good thread worthy of sticky? christopher`s sum up included.
    I have found this very usefull and sure that others new and not so new to enlarging would like this info on hand. regards
     
  13. JCT

    JCT Member

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    I have also found this thread very helpful -- obviously the skills involved in judging or interpreting negatives destined for printing take time to develop, but having a chance to see how others approach this complex process is very useful.

    JT