we’ll finish up on the third way to add contrast to your black and white images. this method isn’t necessarily about contrast, so much as it’s about changing the tonality of the image. adjustments in tonality can also alter the contrast of the image - both the overall contrast, by making the brightest portions of the image brighter and the darker portions of the image darker, but also on a micro-contrast level, making adjoining items contrast more.
this capability - adjusting tonality, and potentially contrast, is available by adjusting the color sliders in your post processing software. in lightroom, look in the hsl area of the develop module. (note: when working with a black and white image it just says b & w) silver efex has a color sensitivity section in the film types section. each of these sections has a number of sliders - one for a specific color: red, orange, yellow, blue, purple and perhaps magenta. moving the slider to the right increases the brightness of the tones of that color within the entire converted black and white image, while moving it to the left decreases the brightness of that color’s tones. this is how tonality of the overall image is modified.
this method can be used to affect the overall contrast, but it’s particularly useful to increase contrast between portions of the image you want emphasized, and to decrease contrast for those items of less importance. if your subject is a dark red fire hydrant surrounded by concrete in the shadows of the sun, (similar tonality) you can increase the contrast between the fire hydrant and concrete by boosting the brightness on the red slider, or reducing the level of the concrete’s tone.
don’t forget that in lightroom you can use the picker in the hsl panel to select the color/tone you want to adjust and it will modify the combination of colors/tones up and down as you specify.
let’s use the following image of a leaf with water drops as an example:
as you can see the tonality of the leaves blends in with the out-of-focus background area. to show more contrast between the leaves and the background i can make the leaves lighter or darker, or the background lighter or darker. (or a combination of the two) as the leaf is the subject of the image and the non-leaf portions are out of focus, i’d rather adjust the tonality of the non-leaf portions. notice in the image below, the red square around the picker in the hsl (now the b & w) panel. if i click on that circle, place the cursor over the item i’d like the tones to change, (the out-of-focus background area) click the mouse and drag up, i’ll brighten the tones. on the other hand, if i click the area i’d like to change tonally, and drag the mouse down, that area will darken. you will see that multiple color items in the b and w panel have changed.
below is the image and the resultant b & w panel after lightening the background using the above method.
as you can see, the leaves, at least the primary leave which is the subject of this image now contrasts a bit better with the background. the resultant b & w panel with the adjusted color levels is shown below.
i like the above image, but i’d like to see what it looks like when the background is darker than the original. so here is the darkened background image shown below:
and its corresponding b & w panel with the updated adjustments:
i actually prefer this version, however you’ll notice the stems were also affected with the tonal changes, making them look a bit unnatural. remember that these adjustments are global so any yellows and greens will be affected throughout the image when the yellow or green slider is modified. you may want to tone down the changes so as not to impact portions of the image you don’t want adjusted, or you might want to use alternative methods other than the b & w panel. (perhaps photoshop with masks, localized brushes to dodge/burn, increase contrast, etc)