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  1. #1

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    Contrast - What does it look like?

    We all discuss contrast, exposure etc but I have to admit that I'm not sure I know what 'Good' contrast looks like. There are some of you that seem to nail your exposures every time, produce images that 'glow', I understand that the the light quality at the time of exposure has something to do with this and that the developing process comes into play. Does anyone have any prints that they could share by attaching them to this thread that would demonstrate, low contrast/high contrast, correct exposure.

    Understand that the scan will lose some of what is there, but would it be any more that is lost through the reproduction in many books? I have seen images that just knock my socks off and other that do not, just based on what I perceive as correct exposure, proper contrast, etc.

    Any thoughts advice, etc is appreciated as always.
    Mike C

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  2. #2
    BWGirl's Avatar
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    I'm with you, Mike! I understand contrast in the non-photo world, but in the B&W world... is it the abrupt change between black & white? Is it sharpness? What the heck is this crazy, little thing called 'contrast' in terms of a picture?

    I hope someone will put something up & direct us to it to explain this in a visual way!
    Jeanette
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  3. #3
    Alex Hawley's Avatar
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    There's been some previous discussions on this. Take a search through the B&W forum here and you should find them.

    Changes in contrast are very important in B&W photography. If you look through the gallery sections, you'll plenty of examples, good, bad, and average. Still its hard to describe. Maybe someone more eloquent can explain. I will simply post two examples.

    The first example is what I would call good normal contrast. Plenty of range between the highs and lows. This particular one has only a few areas in between.

    The second example is very low contrast. So low that I had to pre-expose the paper. The low contrast was caused by a huge burst of steam just before I pressed the shutter. I had set the exposure before the steam burst.
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  4. #4

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    Jeanette, Thank You was wondering if I was the only one who did not understand this.

    Alex, Thank you so much for your post. From your two images I can clearly see that the first is exposed very well, on the 2nd I think it is exposed well, but because the scene has little contrast, then the resulting image is 'low contrast' - Right? Is there anything you would have done different to increase the contrast, exposure vs development?

    Thought I would edit this to explain one of the reason for the post, I seem to be having to print most of my work at grade 4 or greater and seems like I may need to re-visit my personal exposure index. I realize that I could just be chosing to photograph scenes that require more contrast, and that is what I do not understand. Should I be able to expose a scene (correctly) process the film as I always do, then print on grade 2? Or is it not that simple?
    Mike C

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  5. #5

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    Contrast is a very subjective thing... Basically, you are talking about the ability to tell tone from tone, the more contrast, the less middle tones you see, the less contrast, the less extremes (pure white or pure black) you see. Good or bad are imprecise words in and of themselves, so an accurate description of "good" contrast is hard to come by. In practice, good contrast varies with each person's perception of what a print should look like.

    The following picture is quite low on contrast, in part because it was a cloudy day, in part because it was underexposed, in part because it was developed in Diafine. Diafine is a two bath developer, so highlights keep more detail than they would otherwise.

    http://www.apug.org/gallery/showphot...cat=500&page=1

    Although it has lower than normal contrast, it still communicates very well, so contrast is not necessarily bad. The lower contrast simply alters the mood.

    This next shot has good contrast, to my eyes at least. It was also developed in Diafine, but in a better light, and correctly exposed. To me, the contrast is good because all the tones are right where they should be for an accurate rendition of the scene. For some reason the previous sentence smells of BS to me. Maybe accurate rendition is not the phrase to use, but you catch my drift.

    http://www.apug.org/gallery/showphot...sort=1&cat=500

    The attached picture would be the high contrast one. I printed it at about a grade one paper, and the highlights still lost detail. To me, this is the classic "bullet proof" negative. Besides being shot in full (noon) sun in N.E. Brazil, it was over developed (HC-110). This print is still acceptable to me, but the loss of highlight detail is noticeable.

    In all of these, however, the mid-tones where my area of concern when printing. It is my belief that if those are good, minor problems in the extremes can be more easily forgiven.

    As to manipulating contrast, it can be done by manipulating shadow detail in exposure, or highlights in development. Increase exposure, and you get more shadow detail (shadows slowly become midtones). Increase development and highlights become brighter (denser negatives). This is very well explained by Ansel Adams in The Negative. Regardless of your taste for his photography or not, the book is worth a read. I personally don't care for most of his work, but own a copy of The Negative.

  6. #6
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    I do not want to complicate something that you are already wrestling with, but I always have reservations about any discussion of a quality as "good or bad". For example, would you say that some prints exhibit "good grain" or "bad grain" ?? You probably would think that it was good if there was a lot of grain evident and it added to the emotional impact, and conversely, that it was bad if it was just a distraction. My point is that contrast is an element in the creative recipe just like grain and all of the other elements that we use, control, and evaluate in every image that we print.

    If there were such a thing as "universally correct contrast" .... well, it sure sounds like a good argument for handing control over to some automated (dare I say it..???) digigizmo :o

    Which, believe it or not, leads me to the best answer to your question that I can think of: If you like it, it is good.
    If you are familiar with the variables: exposure, film type, developer, developer technique, etc...... then no one can tell you what is "right". It is only possible for someone to either make a comment about their own preference (which you can heed or ignore as you choose), or for someone to answer a specific question about how a certain image could be made to show more or less contrast, if that is what you think it should show.

    Tim R

  7. #7
    Alex Hawley's Avatar
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    Andre said most simply - contrast is sujective and there are no absolutes in good, high, low, or otherwise. It depends on the lighting, the surface textures, the deloper and development, paper - nearly the whole process, AND what you are trying to convey.

    Here's another attachment where there is lots of variation in the surface texture and its tones. I overdid it a bit burning in above the engine to see how far I could push things (also excuse the quick scan dust specs). One reason B&W photogs like rocks so much is that there is a lot of small-sized contrast variations in the texture. Some call this macro contrast.

    Mike, to answer your question, it sounds like you may be under developing. Try increasing your development time by at least 50% and see what happens. Then adjust up or down from there based upon the results. Some of us LF dudes develop by inspection so we look at it as its developing. Still manage to flub it too long or short once in a while.
    Semper Fi & God Bless America
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  8. #8

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    It seems that Tim and I agree on this point. If you are still trying to decide what you prefer in terms of contrast, go to a library or bookstore and look in a few photo books, prefereably not only by different photographers, but by diffrente types of photographers, and different eras of photography (1900's to present, for example). That way you can see a lot of differences in tonality, contrast, print tone, and how they all work with the images at hand.

  9. #9
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    One thing I've been doing recently is working with a Stouffer step wedge for working out development times and contrast with a couple of new films and papers. It really helps to be able to see the actual changes in contrast, exposure and development on one sheet of paper. A "normal" picture taken with the variables in contrast inherent in an image makes it more difficult to judge development times.

    With the step wedge, all variables are able to be controlled and changes are easy to compare because there is no variation within the shot (like shadow values and highlights). All of this is done in a controlled manner which makes subtle changes easier to evaluate and understand.

  10. #10
    Loose Gravel's Avatar
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    photomc,

    You are right, 'contrast' is kicked around alot. It is a very handy word. It is used for lens quality, mtf, image quality, content, many things. In a black and white print I think of it as how fast the image goes from black to white for a given scale in the scene. I remember when I first got started in black and white, I figured that if I had a good black and a good white in my final print, I was home free. And like you, I noticed that sometimes prints glowed and sometimes not. The amazing thing is that prints don't even need to have black or white (pure) to have that glow. A 'grey' print can take on a very nice silver quality that glows. So, what's with that?

    I attribute the glow to 'local contrast' (another term that gets much use). To me this is how well the final prints resolve texture. If you were to take a good negative and print in on several papers, you would notice that some papers do this better than others. In the shadows or the bright highlights, look for details ---texture. If it is there, then you have good local contrast.

    I'm not saying that the glow is in the paper. It takes a good paper to do it, maybe all papers can do it under the right conditions, I don't know. To get the glow you need a good negative and a 'high contrast' enlarging system or use contact printing. By high contrast enlarging system, I mean the total flare of the lens and the enlarger needs to be low. Or, to put it another way, the stray reflections inside the enlarger need to be minimized. It needs to be real black in there and use a good lens.

    Now the negative. Probably the most important. We do a lot of zone system talk here. How much ASA or ISO, contrast, normal, etc. This is important. However, I think most everybody is underexposing their film. They have the right ISO, but the great god Ansel told us to place our shadows on zone 2.5 and so we do. We think this is the law of zones. We think this should work and once in a while it does. However, if there is any texture there, and there usually is, it will become lost. A meter reading that reads for zone 2.5 is an average (over one degree for the spot meter folks). That means that some of the reading is less and some more. On the film, anything short of the 2.5 will have no local contrast (just like the paper). The film curve is just starting to tip up and gain contrast at this point. It just won't separate the fine detail. It will be mushy and mush doesn't glow. Mush has no detail, no local contrast. At the highlight end of the scale, same problem. Some film/developer combos have a maximum density. Above this, more exposure gives no more density. So if there is are little fine details sparkles in something, like wet grass in the sun, those little sparkles are going to be dull. They just don't hold the detail.

    What is the solution to all of this? On the shadows end, the exposure end, it is plenty of light. I don't usually worry about zone 2.5 at all. I am measuring what I think is zone 4. This is usually where the image is more important for me and the negative is really starting to develop some local contrast (getting out of the toe of the film curve). When I'm in doubt, I overexpose by a stop. With large format, this doesn't matter. Largeformatters are usually not worried about grain. With smaller format, do it if you can. Better to glow and be grainy that the other way around. Grain free muddy prints don't get shown. With a well exposed negative, you can burn down the zone 4s to zone 2 and there will be a wonderful quality about them. Dark, yet full of detail that implies light to your brain.

    On the highlights end of things, one needs to pick a film/developer combo that works for them. I would say a compensating developer and a film with a long shoulder. If you don't do this and you do overexpose, then your negatives will block up and that is bad. A blocked negative means the density of highlights in your negative will all be the same and highlight texture will be gone. It's not good to overdevelop, but with the right combo of film/dev, it is not as critical as when you risk blocked highlights.

    There is another glow you see in some artist's prints. Either through lighting or the 'hand-of-god', there is something about the print that is abnormally lighter than it should be. Small amounts of this go undetected, but sometimes it is so strong that it is easily detected as a bad dodge/burn. It is when it is right on the brink that something appears to glow. This is a matter of style and not one of my favorites.

    Now before you all roast me for this, let me say this is only my opinion and that it has worked for me. Your mileage may vary. If this gets the discussion going, that is a good thing. I'd like to put a glowing print up in the apug gallery, but I just got a scanner and I don't think I could get it to glow on a monitor.

    Best of luck.

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