In this first post regarding the Levels and Curve Tools I’d like to emphasize the versatility of these tools. The use of these tools in a raw processing workflow cannot be overstated. In this post I will focus on the basic Levels functions.
Let’s look at this medium contrast image.
The weather was cloudy when I saw this rose on the beach. Low contrast light conditions are fine for close-ups. The water is reflecting the sky and there is some backlight, but that does not make it shine as I intended.
Before using Levels
In my trainings I refer to the Levels Tool as a histogram tool. It takes a histogram as input. Because of this I first apply necessary adjustments that will affect the Levels histogram. For example, I first crop the image; adjust the Exposure, High Dynamic Range (HDR), and Clarity Tool. In the screenshot below, I show you the tools Base Characteristics with film curve, Clarity and Vignetting and their settings.
Black and White Point
Medium and low contrast images do not use all the brightness values, or the full dynamic range of the camera. As a result they look a bit dull because the tonal scale is reduced. There is no real dark or bright area.
The histogram for the image fits easily within the 0-255 range of the Levels Tool. Too easily, actually, and it reflects the lack of both real highlights and deep shadows.
Auto Adjust or manual?
The Levels Tool Auto Adjust is a great start for adjusting the Black and White Levels but you can also set it manually by dragging the markers or use the eye-dropper. The black level sets which level in the raw file will be the new darkest area and the white level for the brightest area on output.
Input vs. Output Levels
To be more precise on what the Levels Tools actually achieves here, let’s clarify the distinction between input levels and output levels. Input levels are found on the bottom of the Levels Tool and represent the values in the raw file. You can see that I did use the range of 11-243 in this image.
Input levels are converted to output levels, which can be found at the top of the Levels Tools.
The input level of 11 is converted to 0 (zero) in the output and input level 243 to 255. Output levels of 0 and 255 represent the maximum black and white respectively. Optionally, you can adjust the output levels as well if it serves your needs, like with printing, to 5 and 250 for example.
The image now has a better tonal scale and therefore more punch.
Darken or Brighten
Setting the black and white levels will change the overall image brightness. This can be corrected with the mid tone marker in the Levels Tool. Modest use has little effect on the endpoints of the histogram. In other words: little risk for clipping or losing data. Positive values open up shadows and reduce the impression of contrast.
A ‘full’ histogram from end to end
Technically the biggest advantage of setting the black and white point plus the mid gray with the Levels Tool in Capture One Pro 7 is that it creates a ‘full’ histogram from end to end on output. This will smoothen gradations without banding (in contrast to setting levels in a processed image).
Also, using Levels precedes the use of the Curve Tool, which I will discuss in my second blog.
High contrast images and Levels
In general, you do not need to set black and white points on high contrast images, which tend to clip at one or either side of the histogram. However, you can still benefit from the Levels mid tone adjustment to make modest brightness adjustments without the risk of clipping. I prefer this to the use of the Brightness slider in the Exposure Tool. Or, as we will discuss in another post, you can also use the Curve Tool for that purpose.
Besides being a photographer in the field of architecture and landscape, Paul prefers to teach and preach the better photographic workflow. He is also a regular contributor to the Phase One moderated user-to-user forums.