Jarrod Erbe is a scientist, educator, and photographer whose images are published in a variety of media world-wide. He shares what he learns about photography and post-processing on his blog and YouTube channel.
What is Post-Processing?
Post-processing is the act of altering a digital image using image editing software. You may have heard it referred to as retouching, photo editing, or even “Photoshopping”. Of course, you may have also seen examples of extreme post-processing that have caused you to question the world around you. While image editing software allows you to push the boundaries of reality, post-processing doesn’t have to be complicated or gaudy. In fact, you may already be post-processing your images without knowing it. If you shoot in .jpg (as opposed to RAW), your camera is making a series of post-processing decisions for you by adjusting exposure, hue and saturation, sharpening, etc., and the image it produces is not exactly the image that you shot.
There is no question that today’s digital cameras are designed to produce technically high quality images. However, images from even the best DSLR or mirrorless cameras can benefit from post-processing. Why? First and foremost, there is more to creating a great image than pressing the shutter. Simply pointing and shooting, even with a top of the line camera, will often result in disappointing images. Then, of course, there are the gremlins associated with any photographic endeavor. Let’s minimally consider the following:
- Operator error. Yes, hard to imagine, but it happens. Have you ever over or underexposed an image? Nailed the exposure but produced an awkward composition?
- Ambient conditions. Sometimes you need to shoot in less than ideal conditions. It may be too bright or too dark. You may be photographing under fluorescent, tungsten or, worse yet, mixed lighting.
- Dynamic range. The human eye has the ability to pick out more details in the highlights and shadows than a camera. How often have you photographed an incredible sunset only to find that the colors and/or details in the scene are not as vivid as you remember them? Produced an unintended silhouette?
How to Post-Process
You have a variety of options for post-processing your images. Adobe’s Raw, Photoshop, and Lightroom software are excellent options and are available on a subscription basis. You might also try Photoshop Elements which is a scaled back version of Photoshop or GIMP, a free and open source image editor.
I prefer to start my workflow in Adobe Lightroom. Lightroom provides several intuitive tools to correct common image problems and, if you plan to expand your post-processing options, offers seamless integration with Photoshop. If you are new to post-processing, I recommend that you start by experimenting in the following 5 areas within Lightroom:
The “rule of thirds” is often cited as a compositional guide. The rule of thirds is easy to follow using Lightroom. Selecting the cropping tool will overlay your image with a grid made up of two evenly spaced horizontal lines and two evenly spaced vertical lines. Placing the point of interest at or near an intersection of these lines tends to produce a more impactful image. Of course, you can also rebel and use the grid to come up with a composition that meets your creative intent.
Another use for Lightroom’s crop tool is to remove distracting elements from the scene. Below is an example of a typical grab shot image – a subject that caught your eye, but not an image that you put a lot of thought into capturing. Even these types of images can be dramatically improved by a simple crop. Notice how the shadow at the bottom left and the bits of pier to the right distract from the sign as the main focus of the image. Cropping out these areas results in a stronger image.
White balance refers to the color temperature of the light in your image. This is a good example of an area where our eyes render a scene in a way that the camera may not. Common tungsten lights, for example, tend to add a yellowish color cast while fluorescent light tends to add a bluish color cast. Under these conditions, our eyes make adjustments so whites will appear to be white. A careful review of your digital images, on the other hand, will often reveal the presence of a color cast. The video below demonstrates how you can use Lightroom’s eyedropper tool to automatically correct white balance. You also have the option to correct white balance manually or to choose from a series of common presets.
Exposure correction may be the number one reason to apply post-processing. Even an image that is properly exposed overall may benefit from minor adjustments to critical highlight and shadow areas. This is accomplished with ease in Lightroom by using individual sliders or working directly in the histogram. Notice how the subtle changes in the highlights and shadows on the puppy’s face make improve the final image.
If you shoot in RAW, you have access to an incredible amount of information in your images. Even severely over or underexposed images can be saved with a few adjustments in Lightroom. In the “before” image below, I exposed for the streetlights leaving the trolley grossly underexposed. The “after” image demonstrates the amount of detail that can be recovered by simply increasing the exposure and opening up the shadows in Lightroom. With a little work, I ended up with an amazing image from what could have been a throw away.
If you like to shoot images that have a lot of texture (e.g. landscapes), a contrast or clarity boost in Lightroom will make your images pop. The contrast slider allows you to increase the difference between the light and dark areas in an image. The contrast slider in Lightroom affects the whole tonal range of the image. The clarity slider, on the other hand, works by increasing contrast, specifically edge contrast, in the midtone areas only. Because the adjustment is limited to the midtones, you can experiment with relatively high levels of clarity. Be warned, however, that not all images benefit from increased contrast or clarity. Portraits, for example, require careful application of contrast or clarity.
While white balance tools allow you to remove an overall color cast, you also might want to adjust specific colors within your image. A series of color sliders give you complete control over the hue, saturation, and luminance values in your image. What if you don’t know exactly which color to tweak? Lightroom’s clever targeted adjustment tool automates the process for you. By selecting a specific area within the image and simply dragging up or down with your mouse, you can quickly change the hue, saturation, or luminosity of that color within the image.
I find that post-processing allows me to make images that more closely resemble my vision at the time I pressed the shutter. The ability to effectively post-process your photos will improve your photography. With Lightroom, Photoshop, and all the excellent third party plug-ins available, your creative power is limited only by your imagination.