Have you ever had the highlight areas in the sky turn out all white and blown out in a shot, although it didn’t look that bright in real life? That happens because the range of colours and tones that a camera can capture (known as its “dynamic range”) is narrower than that of the human eye. Here are 4 mini lessons that will help you to understand dynamic range better, so that you can avoid blown highlights and retain more detail. (Reported by: Chikako Yagi, Digital Camera Magazine)

EOS 5D Mark III/ EF70-200mm f/2.8L USM/ FL: 150mm/ Aperture-priority mode (f/6.3, 5 sec, EV ±0)/ ISO 100/ WB: Shade

 

Lesson 1: Learn to identify where it’s okay to have blown highlights

Generally speaking, a photo with good exposure will have no blown highlights or crushed shadows, with all the tones within the dynamic range of the camera. However, there are certain scenes where it is acceptable to have some blown highlights.

For example, when you are shooting directly into the sun, there is no way you can avoid the sun from being blown out. If you tried to reduce the blown highlights, it would throw the overall image off-balance.

Meanwhile, some other subjects, such as waterfalls, streams, or seas of clouds, are also prone to blown highlights, but contain details in highlight areas that are important to the scene. For such scenes, you will want to take exposure carefully, and shoot a little darker than the classically “correct” exposure.

Example 1: Sea of clouds in the morning sun

1) Sun: Blown highlights are acceptable here
2) Sea of clouds: Avoid blown highlights here

There is a natural gradient of colours around the sun. Leave the blown highlight as it is to keep the balance. However, the details of the clouds are what makes the sea of clouds so impressive, so be careful to retain them.

Example 2: Sunbeams in a forest

1) Leaves and cobwebs in direct sunlight: Blown highlights are acceptable here
2) Sunbeams: Avoid blown highlights here

This image looks so expressive because of the light falling on the mist. Make sure that the details in the sunbeams are retained. The blown highlights in 1) show the shape of the cobwebs, so they are acceptable here.

Find out how an ordinary black umbrella can help enhance sunbeam shots in:
2 Everyday Items That Could Transform Your Photos
Also see: Sunrise, Sunset: Achieving Dramatic Contrasts in Street Photography

 

Lesson 2: Use the histogram to help you decide on the exposure

The histogram is a graph that shows the distribution of the pixels in your shot according to their brightness. If your image has many bright pixels and is overexposed, the peak of the histogram will be at the extreme right. Try not to let the histogram be clipped off at the right.

Blown highlights

This shot was exposed for the balloons, but the shot is overexposed as a result. The histogram suggests this too: Notice how the entire histogram is skewed to the right. The peak is clipped off at the right, which means there are a lot of pure white pixels, indicating the presence of blown highlights.

No blown highlights

This shot was exposed for the sky: The cloud details are retained. The peak of the histogram is nowhere near the extreme right. In fact, all the pixels are safely far away from the corners. This is the “standard” exposure.

Tip: Use a tripod

If you are shooting by hand, it can be challenging to keep your composition straight while engrossed with using the histogram to fix your exposure. Use a tripod to help.

 

Lesson 3: Use Auto Exposure Bracketing to shoot the same image with different brightness

Using the Auto Exposure Bracketing (AEB) function helps you take three exposures of the same shot with incrementally different brightness, all with the press of one button. This is great for rapidly changing scenes when you are not completely sure which exposure settings will work best.  From there, you can choose the shot with the most appropriate exposure.

EV -1

EV ±0

EV +1

Learn more about this in:
Camera Basics #4: Exposure Compensation

Know this: You can merge the AEB exposures in your post-processing software to create an HDR (High Dynamic Range) image. 

 

Lesson 4: Shoot in RAW and make adjustments during post-processing

A RAW image file contains much more information than what you see your Live View/EVF preview. You can recover a significant amount of detail from it during post-processing, although to what extent depends on the shooting conditions. Don’t forget to refer to the histogram when you edit your shots!

Correcting blown highlights

Step 1: Check the histogram to see if it is clipped on the extreme right
Step 2: Decrease your “Highlight” and/or “Whites” parameters

Have you heard about the HDR PQ HEIF format? Find out why it is said to be the image format of the future in:
HDR PQ HEIF: Breaking Through the Limits of JPEG

 

How to check for blown highlights

1. Display the histogram during image playback

You should be able to display the histogram and RGB charts in image playback. This will allow you to see if your image has blown highlights due to overexposure.

Tip: You can usually toggle through various playback display screens by pressing the “INFO” button located on the back of the camera. If you still can’t display the histogram, press the "MENU" button, go to the PLAYBACK (blue) tab, and look for the “Playback information display” item to make sure that the histogram screen is activated.

2. Make use of the Highlight Alert

If your camera has the Highlight Alert function, turn it on. The blown-out areas in your shot will blink black in playback (hence, they are also called “blinkies” or “zebras”). On camera models that don’t have the “Highlight Alert” function, the blown out areas will also blink black on the playback screens that display the histogram.

If a huge part of your image is blinking in black, that is a sign to reshoot with a darker exposure.

 

Reflection shots can really test your skills about where to take exposure from and how to get the appropriate exposure. Learn how some professional photographers achieved their works here:
Reflections: A Castle at Night with the Trompe l'oeil Painting Effect
Reflections: Dazzling Red Mount Fuji (with Retouching Tips)
Reflections: A Steam Train Rides Off into the Dramatic Sunset

 

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