I’d like to start this off with a warning. I only have a few years of experience with film and darkroom printing. I’ve learned a lot since I started, but this whole post might be completely false. Regardless, I feel like the results I get match what I’ll explain.
So there has been a number of things I consider myths propagated in the modern film community. There’s also been a number of modern things not properly explored by the photographers of old. I’d like to propose counter theories to these, and give some understanding of how each component in an analog workflow actually relates to the final end result, ie, the print.
The Print
Oddly, I’d like to start here, the final aspect to the actual result. Understanding how a negative translates into a positive print is important for understanding the rest . The modern invention not discussed in enough detail previously is multi-grade/variable contrast paper. Each manufacturer implements this in a different way, I’ll be focusing on Ilford’s method specifically because it’s what I’m most familiar with, but all the methods mean mostly the same thing.
I dare propose a new axiom for printing: “Expose for the highlights, adjust contrast grade for the shadows.” Exposure controls when highlights “clip” to white, while the contrast grade used controls when shadows clip to black. This means that too much contrast means there is very little shadow detail while too little exposure means there is very little highlight detail. There are limits to each. There is only contrast grades from 00 to 5. For exposure, if you have too little, no contrast grade will permit reaching a proper black, while if you have too much no contrast grade will avoid some shadow detail clipping to black. I’m not covering contrast masks, dodging, burning, and other techniques here. Many great authors have already covered these concepts, I’m only talking about the much easier “straight” prints that only involve exposure, development, and fixing. Split grade is another useful too, though it’s hotly debated if split grade printing is anything more than just the equivalent of fractional grades between grade 00 and 5.
Manufacturers that I’ve done step-wedge tests with to determine contrast grade behavior:
Ilford — Increasing grade makes shadows darker, including deeper shadows clipping to black. It also makes the lower midtones slightly darker.
Foma — Increasing grade makes everything from middle grey darker, and functions in a very linear way
Adox — Increasing grade makes deeper shadows darker and some clipping to black. Compared to Ilford it doesn’t have as much effect on upper shadows, but still has some effect.
So, if you’re starting with what looks like a properly exposed print, here is a quick way to deal with contrast problems.
Shadows too dark, highlights are perfect — Decrease contrast grade
Shadows too light, highlights are perfect — Increase contrast grade
Shadows are too light and highlights are too light — Increase exposure and potentially increase contrast grade
Shadows are too dark and highlights are too dark — Decrease exposure and potentially decrease contrast grade
Shadows are too dark and highlights are too light (or not enough detail) — Increase exposure and decrease contrast grade
Shadows are too light and highlights are too dark — Decrease exposure and increase contrast grade
Without delving into developer formulas, there isn’t really a method in printing to modify highlight contrast, and midtone contrast control can be quite limited since it is tied directly to shadow contrast. This means to control these without more advanced techniques, we need to control these on the negative. (note there most definitely is chemical ways to modify highlight and midtone contrast, but assuming you’re using off the shelf print developers, there’s very few options that make any significant difference)
The Negative (and film developer)
I won’t go all into the different films. There’s plenty of guidance for choosing the right film… I’ll instead discuss the characteristics to look for depending on what you want that final end result, and what you can do in developer choice and process to get closer to those desired results. These are the characteristics that a final negative can have:
Density scale — This related, but often confused with contrast. Scale basically means how “compressed” the information in a negative is. This is how dark (in negative terms) the deepest highight (dmax) is compared to how light the most shallow shadow is (dmin). To see this in action, compare a high contrast color negative film exposure compared to a low contrast slide film exposure. Despite the slide film typically being regarded as higher contrast, the darkest spot on slide film compared to the lightest spot will look much further away compared to the color negative film.
Contrast curve — This is complex, but if you plot density in relative terms between dmax and dmin, this is the way that density builds up in comparison to exposure level… Tackling this entire concept is a bit much, so instead I’ll just discuss the key components:
Highlight contrast — In more technical terms this is called the “shoulder” and related to the concept of “highlight compensation”, ie, where some developers and film types “slow down” in the highlights and become lower in contrast
Midtone contrast — This tends to be what people think of as the broad term “contrast”. How many different shadows of middle grey there are
Shadow contrast/speed — In technical terms called the “toe”. This is how quickly the lesser exposed shadows build up density to reach “midtone” in appearance, and is in many ways related to the perception of a film/developer combo’s “speed”. If shadow density builds up very slowly while everything else is normal in contrast, a film will often look under exposed, even if the information is all actually there.
Grain — This is how grainy an image looks. Often how “grainy” an image appears can be very different in shadows and highlights
Sharpness — This is how much detail the film has. It is often a direct trade off between either keeping grain or sharpness and rarely both, though graininess can sometimes be “hidden” with contrast and scale tricks, and unsharpness can in someways be hidden by definition
Definition — This is more strongly related to sharpness, but is more in like the digital terms of sharpness. Definition can make larger details appear to be sharper. This tends to be through what are called edge effects and adjacency effects. Some developers, especially tanning developers, will exhaust “around” highlights, resulting in adjacent shadows having a thin line of under development compared to the rest of the shadows. This is often a very difficult thing to measure objectively.
Both film type and developer can affect all of these characteristics, but each limit the other. For example, making a low contrast film into high contrast is often quite difficult and comes with compromises.
One myth I’ve seen is that one should always aim for low contrast because “you can always add more contrast afterwards”. There is a little bit of merit. Specifically a lower contrast aim means that you’re less likely to lose detail by mistakes in exposure, and it’s pretty difficult to really get to the point of needing higher than grade 5 in printing. In short, aiming for low contrast is easier. There’s little risk of clipping by over exposure, you can easily print high contrast landscapes such as sky+forest, and there is often a smoothing effect that low contrast has that is highly desirable for most portrait work.
That being said, a low contrast aim can come with serious compromises that are often overlooked. Low contrast typically comes with a short density scale. This may mean that getting all of the detail onto paper is easy, but compression is a cost. I can’t confirm it exactly, but in my experience, short scale negatives tend to print excessively grain. Increasing contrast during printing in general tends to give more perceived grain. Also by aiming for low contrast, you’re typically leaving some tonal information from the subject behind after pushing the shutter. Those rich tones instead become a much more compressed sea of almost but not quite middle greys. The other important thing to remember is that it’s often not possible to modify highlight contrast nor midtone contrast easily in printing. So, a low contrast aim in the negative can ruin something that needs a rich level of highlight detail on the print, even if all the detail is “there.”
The old axiom “expose for the shadows, develop for the highlights” is as accurate when it was made as it is today when working with modern materials. You need to expose the film enough to get all that shadow detail that is needed, while developing to get the appropriate amount of highlight (and midtone) contrast. Negative contrast can be modified in some ways by doing things such as selenium toning the film, but it’s better if you can get it right from the start instead of needing to “rescue” an image.
Making sense of it
Basically, you have two points at which you “compress” tones. There is the negative and the print. A low contrast negative is compressed and typically “decompressed” in printing by increasing contrast. Alternatively, a high contrast negative is uncompressed and typically compressed in order to fit all the appropriate detail onto paper by using a lower contrast grade.
I’m by no means saying that every negative should aim for high contrast nor that low contrast doesn’t have its uses. My point is rather that high contrast aims in a negative has its purpose and “aim for low contrast” should not be the automatic choice. Unfortunately, most commercial developers today are aimed for lower contrast, at least using advised instructions. Most are also automatically compensating developers to at least some extent. This means more developer/exposure means highlights get compressed into some developer constrained maximum density. This is a natural side effect of chemistry and to not include any compensation requires specialized formulation which may be less commercially useful. Regardless, there are some which have this effect to a minimal amount. Commercial developers I’ve tested to have minimal or no compensation are HC-110 B and Rodinal 1+25. D-76 stock is also much less compensating than D-76 1+1.
With a non-compensating developer, you have to worry about literally clipping the highlight detail into the film’s theoretical dmax, not just some developer constrained dmax. Such a developer is typically high in activity, and in many cases can even be abused to work as a print developer.. ie, it can give proper black tones on paper given extended time. Most developers can not give this at film dilutions within a reasonable amount of time, like say 5-10m.
So what is possible?
The key thing to tie this knowledge into is to apply to get what you want on the final print.
Low contrast, compensated negative:
Mid to high contrast control in shadows — You’re typically going to be stuck with somewhere from normal to high contrast shadows depending on the grade you use, that is, assuming you want to get a proper black in the deepest shadows. Going too low in grade to decrease shadow contrast means that you’ll need more exposure to get a proper black level and highlights may be darker than likely wanted, while also appearing to increase grain
Low contrast highlights — Because highlights can not be easily manipulated in printing, you’re stuck with lower contrast highlights which explicitly occupy the highlight tonal range (ie, not possible to move them to upper midtones easily)
Superior midtone contrast control — Midtones can be moved in and out of shadows easily since it occupies so much of the image range, so it is typically fairly easy to manipulate the contrast here
High contrast, uncompensated negative:
Superior contrast control in shadows — It’s easy to go overboard and be limited in contrast control (ie, you only have 00 but need 0000 grade), but done to the proper level, can enable unparalleled shadow detail with soft low contrast shadows that properly appear with black levels floating smoothly in and out of the shadows rather than some details simply clipping into black.
High contrast highlights — same as elsewhere, you’re stuck with what is on the negative for the most part. In order to avoid a mess of clipped whites, you will need quite a bit of exposure but not so much that you’ll lose shadow details if you want moderate contrast there.
High contrast midtones — because separation between shadows and highlights is so large, there is relatively little midtones and so they will be consistently higher in overall contrast appearance and can easily be moved in and out of the highlight tonal range.
High contrast, compensated negative:
Decent contrast control in shadows — The compensation causes highlights to not be as far away, so contrast control will be more limited in shadows, like a low contrast developer, but shadow contrast will naturally be higher and if the compensation isn’t too much, there is still plenty of potential here for softer shadows
Low contrast highlights — Because of compensation, highlights will be much lower contrast and difficult to move into upper midtones without clipping shadows.
Normal to high contrast midtones with some control—Separation between shadows and highlights are still rather high, but typically highlights are less dense than with an uncompensated developer, meaning that contrast of midtones will be lower than with a high contrast uncompensated negative.
Applying these guidelines to more practical situations:
Classic foggy landscape — High contrast processing will allow you to maintain that subtle fog detail and separation in the highlights without it just looking.. well, like a mess of grey
Crude (ie, outside of the studio, maybe) flash portraits — Low to normal contrast with highlight compensation will allow you to deal with the exposure errors likely with unplanned flash shots and smooth lower contrast highlights on the face is typically an attractive look. The exception here might be concert kind of shots where you want a high contrast gritty look and intend to clip a lot of shadow detail to black to emphasize the person on stage
Sunny partly cloudy sky landscape, without filtration — This highly depends on what is wanted from the scene. Low contrast and darker landscape with very brilliant clouds, you’d want a higher contrast uncompensated developer. If the aim is to get a higher contrast and brighter landscape with the clouds there but less emphasized, then a low contrast developer. If you want the clouds more emphasized there, then you’d probably need a red or orange filter.
Basically the big key thing to consider is how much shadow contrast you want and how you want the highlights to look and if you intend to clip any of the usable detail into white or black on the final print for dramatic effect.
Both whites and blacks on a print can be quite eye catching and so using them should be done with care. For whites especially, this can involve a very stand out tonal shift. For example, a paper’s base might be a very bright white, but the closer highlights to be a slightly yellow warmer tone on this paper. This kind of eye catching effect can be extremely powerful but must be used carefully. For black tones, there is often at least some on most prints, unlike whites. They are less eye catching but only if shadow contrast is kept low. If shadow contrast is fairly high, then this too can be quite eye catching with subtle lower midtones poking through a sea of black. This can be exploited for great artistic purposes, but can also be distracting if poorly used.
These topics are covered in detail in the famous Ansel Adam’s series of books, The Negative and The Print. I highly recommend reading them for a lot of practical advice on how to consider the use of variable contrast in film development in a variety of real life situations, as well as many other topics on building your photography skills. Personally I believe that the zone system is overly complex and overrated, but the zone concept is basically what I’ve said here in a whole lot more words. I think that understanding it is valuable even if you never actually use it in the field.