How many of you spend many hours and much creativity getting the image as perfect as possible in camera, then return to Photoshop or similar and use the brightness, contrast and color controls for your post production. If this sounds like you, then maybe you should have a look at the levels control in your editing program. Whilst this is not intended to be a tutorial on the levels controls, I will explain briefly how to use them before explaining why you should use them
The Histogram is Your Friend
If you have seen the levels controls before and been daunted by it, don’t be. Perhaps the scariest element of levels is that strange looking graph called the histogram. In fact this is your best friend and like all best friends it takes a little time for your relationship to develop but in the end it will be rewarding and long lived.
The histogram is basically a graph that shows your exposure. Think of it as a bucket full of light. At the left end you have the darkest parts of the image, and the right the lightest. Your goal is to have the bucket full but not overflowing.
At the left end of the histogram you will see a small triangle moving this to the right will increase your black levels. You aim is to bring it as close to the beginning of the graph as possible. Similarly at the right end is another triangle by moving this to the left you reduce the density only for the highlights. The middle triangle represents the mid tones of the image, drag that left to lighten the mid tones and right to darken them.
So why should you use the levels rather than the brightness/contrast and color controls? Well put simply it gives you a huge amount of control over your image, much more than you may think at first glance. When you use brightness and contrast your editing program is controlling an image using a fixed inflexible algorithm. It simultaneously changes dark mid and light tones in all three colors with little or no control.
By using levels you can control exactly how you want the dark, light and mid tones to look. By compressing your bucket of light, you can infinitely tweak the contrast. Using the included eye dropper tools you can define your black point, white point. Between the white and black point droppers you have the grey eye dropper. By clicking this on a neutral grey tone in your image, you can quickly correct a colourfast.
Boosting the Contrast
Controlling the grey point brings us onto the next advantage of levels and often under estimated tool, color control. When you first open the levels palette you will find the histogram shows the overall RGB levels. Look closely at above the histogram and you will see a drop down box. This allows you to individually see the red/green/blue histograms and adjust them individually.
Why is this important, well let’s say you have a blue cast in a shadow that is spoiling your image. By selecting the blue only histogram, you can move the black point a little to the right, this would add yellow to the blue shadows only, and neutralize the cast.
The levels tool become even more powerful when you combine it with the selection tools. For instance if you wanted to warm the tones of a grey building but keep the rest of the image the same color, you could select just the building, open the levels dialogue, use the mid tones blue or red slider and warm up the greys. The rest of the image will remain exactly as it was.
Using a selection to enhance the red face by Jason Row Photography, on Flickr
In some imaging programs such as Photoshop CS5, the levels control has a series of presets to base as a starting point, for instance, increase contrast or lighten the midtones.
There are a multitude of things you can do with the levels controls, so why not take a look and see what you can do. Remember to work on a copy of your original, just in case you get a little carried away and end up with a Hockney rather than an Adams.
Jason Row is a British born travel photographer now living in Ukraine. You can follow him on Facebook or visit his site, The Odessa Files. He also maintains a blog chronicling his exploits as an Expat in the former Soviet Union