Level 2 Plus

Lesson 10

Levels and Histograms

This lesson will provide a foundation for an understanding of how to evaluate exposure in our images. The next two lessons will build on this understanding, providing us with techniques to correct exposure.

Introduction

In this lesson, you will learn that the “Histogram” in our cameras and the “Levels” function in Elements both give us exposure information about our image.

You will learn to evaluate our images and their corresponding “Levels” displays. We will discuss balanced exposure, light exposure, dark exposure, overexposure and underexposure; as well as how to distinguish them.

We have selected a balanced image from the “Photo Well”.

From the Main menu, we clicked on:

[ Edit ]

From the drop down menu, we clicked on:

[ Go  to Standard Edit ]

In the “Standard Edit” screen, we have moved to the Main menu & clicked on:

[ Enhance ]

Then we clicked on:

[ Adjust Lighting ]

Finally we clicked on:

[ Levels ]

We have selected a balanced image from the “Photo Well”.

This image is balanced in the sense that it has a full range of tones from near black to pure white, as well as all the tones in between.

In your camera, you can see the various tones in each of your images on the LCD screen on the back of the camera.

In the camera this display is called a “Histogram”. If the image is not adequately exposed, this information may guide you to retake the image.

In Elements, the same display is called “Levels”. If the image is not adequately exposed, this information may guide you to fix the image.

Fixing the image happens on the “Levels” screen and will be discussed in Lesson #11.

The point at the far left side of the graph is called the “Black Point”. It represents 100% Black.

The point at the far right side of the graph is called the “White Point”. It represents 100% White.

Zone #1 = mid-tones

Zone #2 = dark shadow areas

Zone #3 = bright highlights

The height of the graph shows how many pixels in our picture are in each tone.

This image, and its “Levels” display, illustrates a balanced exposure with most of the exposure in the mid-tones and less information in the very light and dark areas.

This image is correctly exposed.

This image, and its “Levels” display, illustrates a light exposure with most of the exposure in the bright tones and less information in the mid-tones and even less in the dark areas.

This is a light subject, therefore this image is correctly exposed.

This image, and its “Levels” display, illustrates a dark exposure with most of the exposure in the dark tones and less information in the mid-tones and even less in the light areas.

This is a dark subject, therefore this image is correctly exposed.

This image, and its “Levels” display, illustrates a balanced exposure with most of the exposure in the mid-tones and less information in the very light and dark areas.

This image is correctly exposed.

The image in the far left pane is underexposed.

The Image in the middle pane is correctly exposed.

The image in the far right pane is overexposed.

This is the correctly exposed image and it’s balanced “Levels” display.

This image does not need to be fixed in “Levels”.

This is the underexposed image and it’s dark “Levels” display.

This is the overexposed image and it’s light “Levels” display.

This is a dark “Levels” display reflecting an image that is dark.

The “Levels” display looks similar to the one in the next step. We need to look at the images to differentiate.

The image is a normally exposed dark image not in need of repair.

This is a dark “Levels” display reflecting an image that is underexposed.

The “Levels” display looks similar to the one in the previous step. We need to look at the images to differentiate.

The image is an underexposed image and in need of repair.

This is a light “Levels” display reflecting an image that is light.

The “Levels” display looks similar to the one in the next step. We need to look at the images to differentiate.

The image is a normally exposed light image not in need of repair.

This is a light “Levels” display reflecting an image that is overexposed.

The “Levels” display looks similar to the one in the previous step. We need to look at the images to differentiate.

The image is an overexposed image and in need of repair.

Summary

In this lesson, we learned that the “Histogram” in our cameras and the “Levels” function in Elements both give us exposure information about our image.

We learned to evaluate our images and their corresponding “Levels” displays.  We discussed balanced exposure, light exposure, dark exposure, overexposure, underexposure and how to distinguish between these terms.