253 Shades of Grey

Birds of Chicago in concert at CSPS Hall, Cedar Rapids, IA.

No, I'm not talking about a souped up version of the provocative novel. I'm talking about the Zone System.  Developed (pun unavoidable), by Ansel Adams and Fred Archer as a method of visualizing a scene and then processing the negative and print in a way that optimizes the image as it appears in monochrome, it has been the de facto standard for many photographers when it comes to black and white for over seventy years. The original Zone System broke monochrome images down into nine levels of grey, plus black and white. Digital allows much more discrete delineation, with 253 levels of grey plus black and white.

I'm not going to go into detail on how the Zone System works, for three reasons. First is that it's so involved a method that entire semesters in college are devoted to it.  Second, because it is based on using film, not digital, there are common principles involved but not direct correlation of certain things. Third, this article is meant for the average camera owner to find out ways to have more fun, and a lengthy discussion on the Zone System isn't  that fun for the average person as far as I'm concerned.

What I am going to do is provide some tips on how to convert color images into monochrome, or black and white as more popularly labeled. I often have people tell me they like some of my monochrome images more than the color ones. Monochrome, done right, certainly evokes a different mode and set of responses than color. The reason for this is because when color is removed from an image, what is left are "pure" elements of light and shadow (contrast) form and emotion.

Some people look at an image they've taken and think about what it might look like in black and white. Others never give it a thought, but should. Sometimes a photo that is just blah in color becomes much better when converted to black and white. The conversion must be done right, though, for the image to really improve by being converted to monochrome.

Just about all digital cameras and smart phones have a monochrome option among the settings. This is the simplest way to shoot black and white, and I would recommend using it if you don't have access to or want to use an editor, but even more so as a learning experience. Capture a scene in black and white on the spot, and you have the opportunity to see what it will look like. This helps train your brain to visualize scenes in black and white. That's what the Zone System is meant to do-train how to see things-and there are even filters you can buy which make a scene appear as it would when converted to monochrome.

That said, I recommend against using in camera monochrome to produce monochrome images, with the possible exception of if the device also offers an option as to what color filter is applied (more on that in a bit). The reason for this is because few color scenes simply convert straight to monochrome without certain tweaks and adjustments. Ever see some black and white photos that are simply breathtaking, while others are blase? There are usually two reasons for this. First, the subject doesn't really lend itself to monochrome. Second, the image was probably just subjected to a "Black and White" module in an editor without any tweaking done.

Once upon  a time, to do quality monochrome conversion in digital meant breaking the image up into layers of cyan, magenta, yellow and black, then mixing the ratio of each layer to come up with the desired, final result. Then came channel mixing. Some people still use these techniques. Now, however, apps and plug ins are available for both computers and smart phones that make monochrome conversion both easy and effective.

(Note: Depending on your browser and monitor settings, differences in images may be more or less pronounced. Best to view this with the latest version of Internet Explorer or Firefox.)

Back in the film era...

The tweaking doesn't have to be complicated to get a good black and white image from a color one. When using black and white film, it was common to use a colored filter over the lens to alter the way in which the film recorded the colors in monochrome. Common filter colors were (and still are) Red, Orange, Yellow, Green and Blue. These filters would pass all of the main color, but cut down the other colors of the spectrum in varying degrees. Here are some examples:

Here's a couple of images in color to see how the various hues convert to black and white.

Straight conversion: All hues are converted directly to the closest monochrome equivalent. Skin tone is a bit too dark, vegetation too light.

Red: Greatly darkens blue skies and foliage, while lightening most skin tones. Great for landscapes, use sparingly on portraits. Notice how much the yellow blossoms stand out compared to the straight conversion?

Yellow: Darkens skies and foliage but not as much as red filter, Skin tones are actually a bit closer in tonality to color version. Best choice for all around black and white photography/conversion.

Orange: Intermediate effect between red and yellow.

Green: Lightens blue skies, foliage turns almost white. Brings out details in skin tones, so it can make a male subject look more swarthy but be unflattering to female subjects.

Blue: Similar effects to green, only more intense: blue skies turn white, foliage stays about the same, skin tones can look ugly. Turns light skin very dark.  Used rarely, but can be good for architectural and other scenes where a unique contrast is desired. See how the yellow blossoms are now darker than the rest of the plant?

Apply changes in brightness and contrast along with filters to get the final result you like.

So you can see, if you have a monochrome conversion application or plug in that allows use of colored filters, or to adjust how the application "reads" the balance of colors in the image, it only involves a couple of steps or sliders, and a bit of experimentation to see which settings you like best. For most people and most photos, we can end this discussion here. You've learned as much as is needed to cover the majority of situations where a satisfactory black and white conversion can be done. Tweak a bit of brightness or contrast, sharpening if necessary (remember to always save sharpening for the final step) and you have turned that ordinary color photo into a black and white masterpiece.

A note about printing: If you want the best results when printing your black and white images, do not take them to a lab that will just print them as color images. This can result in unwanted color casts or changes in how the print looks. Have a lab do them that offers black and white specific printing for the best results.

That's about it. Almost...

The following is for those who want to do a bit more tweaking to come up with images that stand out even more, or are more difficult to convert.

Throw 'em a curve, and a slider.

When using film, contrast and tonal curves of the negative were determined both by the film itself and how the film was processed.  Then the right paper had to be selected, as print paper came in a variety of contrast grades, which themselves varied from manufacturer and "model" of paper. A decently stocked dark room might have a dozen or more different types of paper on the shelves.

Digital is so much easier. For the most part, all the factors involved in selecting the type of film, how to process it, and what paper to use can be handled by the "Curves" adjustment found in more advanced editors such as Lightroom, Photoshop , Paint Shop Pro and others. (If you use Photoshop Elements, which lacks curves adjustment, there are plug ins you can use).  Simply put, every image has a tonal curve, that represents that relative brightness and darkness of various parts of the photo compared to the theoretical limits of bright and dark. (That's as tech as I'll get in describing curves.)

What the curves tool does is let you alter that curve so that a dark part becomes darker or lighter, or light parts become lighter or darker. What might involve several choices of film, chemicals, temperature, agitation and paper type in the old days can be done in seconds with a slider of the curves tool. One precaution regarding the tool: it can get out of hand if you try to adjust too many points or adjust them too much. Less is more when it comes to the curves tool.

Straight conversion, no curves. Image is slightly underexposed.

Curves applied to bring up the middle tones and highlights while leaving the shadows relatively unchanged.

Do your level best.

Another nice tool is the levels tool. It's similar to curves, but affects the entire image at once, whereas curves affects only certain areas. The tech behind it is that each image, ideally, ranges from the blackest black to the whitest white were detail is still barely visible. This doesn't always happen, due to exposure being off. An image may be too dark or too light.

The levels tool offers a graph which shows where the various dark and light parts of an image fall along a graph, and how intense each segment is. Ideally an image should stretch all the way from the left side of the graph (0) to the right (256), with an even distribution of tones. When you open up the levels tool, you will see that you can use a slider to adjust two things. One adjustment lets you "stretch" or "compress" the image to fit within the levels range in the way that gives it a balanced contrast range. The other is to tell the editor what you want the midpoint or overall range of tones to be. Both will cause changes to the overall image in regards to contrast and relative brightness of the darkest and lightest parts of the image.

I personally don't use the levels tool nearly as much as the curves tool, in part out of personal habit and partly because I make sure I get the exposure as close to ideal as I can at the time of capture.

Levels tool was used to adjust the midpoint and highlight point to correct underexposure. Note how, while this does bring up more detail, it also results in a flat looking image.

And then some other stuff happens.

Curves and levels tools alone can take the quality of any image up a notch when it comes to contrast and tonal curve or gradation. Then there are some additional steps that can tweak an image even more. I won't go into detail, but will summarize a few tools.

Burn/Dodge: Precisely adjust the darkness or brightness of specific elements in the image.

Tone Map: Digital alchemy at it's finest. A tool which breaks down the tones of an image into a different number of parts (ranging from 1 to 256) and then allows  you to increase or decrease the contrast between each part. If you have this available, play with it to see the sort of interesting effects that result.

Shadow/Highlight adjustments: Tools which adjust shadows or highlights in relationship to the overall image brightness. What is adjusted is altered by changes in the levels, so used in conjunction with the levels tool, this can make a big difference in how an image looks.

Black/White  Level: Different from shadow or highlight, it effects the prominence of black or white within an image, independent of the level of the overall image.

Toning: Black and White allows for a wide variety of tones to be applied. Sepia is the most common, but there are also various tones such as Platinum print, Albumen, Cyanotype, Opalotype and many more. Keep in mind that toning can also effect the overall contrast and tonality of an image, so you might have to experiment with all the other settings to get the exact results you want.

Keep in mind you can also select only certain parts of an image to apply any of these tools mentioned, from curves on down. Also, working with various layers and different layer transparencies can have a major impact on the final image. A "Gallery quality" black and white conversion might involve hours of working with various tools on several layers. Or it may not. It depends on the starting image and goal for the final image.

Here is an image which combines a lot of different techniques. In addition to converting with a red filter to increase contrast a bit, curves adjustment and tone mapping, and sepia tone were used to give the image more impact and emphasize the gritty feel of the radiator and texture of the wall. It's also not 100% desaturated: I left in just a bit of the original color.

Fortunately, most modern editors offer enough basic tools that are simple to use for most people to create monochrome images that will both satisfy your creative urges and impress viewers. If you really get into monochrome conversion, there are several apps that can be used as plug ins or even stand alone converters. My preference is Topaz Labs BW Effects. Another excellent one is Nik's Silver Efex Pro. Some "film emulators" such as DxO Filmpack can simplify monochrome conversion by letting you choose a specific black and white film, and make minor adjustments.

Look for images that you think will look good in black and white. Experiment, have fun, and do Ansel Adams proud.