Dynamic Range

Have you ever wondered when you enter a dark room with only a faint glow of light coming through a small window? You strain your eyes, trying to make out the details in the darkness, but then something incredible happens, your eyes adjust and you start to see objects around with better clarity. Well, that ability of the eyes is called dynamic range.

Dynamic range refers to the range of brightness level a camera can capture from the darkest shadows to the brightest light. It is measured in stops.

I understand this concept is quite confusing, let’s understand it with an example:

Imagine a person sitting next to a window in broad daylight. One side of their face is darkened by shadows, while the other side is bright due to sunlight. If you see it with your eyes you will have better details than if you try to capture that image with a camera. Do you know why? It’s because our eyes have a dynamic range of approximately 20 stops. Right! No camera has so far managed to beat that. Even high-end cameras offer a maximum of 15 to 16 stops.

I believe by now you have got an idea of what dynamic range is. Now, let’s understand the concept of stops.

To understand stop, we have to understand what aperture is. Soon, I will be creating a video on the exposure triangle, which covers the three essential elements ISO, aperture, and shutter speed that are responsible for achieving proper exposure in your image. For now, just understand that aperture refers to the opening of the lens. The larger the aperture, the bigger the opening, which means more light enters through. The f-stop is a measure of the amount of light that enters through the lens opening. F-stop values are expressed as fractions, so a larger f-stop number represents a smaller f-stop value, which means a smaller amount of light, while a smaller f-stop number indicates a higher f-stop value, which means more light.

To understand F-stop better, you can refer F-Stop, here I have explained F-stop and its significance in detail.

Now, let’s consider the factors that play a role in achieving a good dynamic range. When we press the record button, the lens aperture opens, allowing light to enter and hit the camera’s sensor, which then begins processing the image, then with the help of various recording profiles images are captured. However, these are not the only factors that impact dynamic range; lighting techniques and color grading also play significant roles.

Let’s understand how these factors influence the dynamic range.

Camera Sensors

Cameras with larger sensors offer better dynamic range compared to a camera with smaller sensors. Full-frame cameras, medium format cameras, and some high-end APS-C cameras are large sensor cameras in terms of physical size, allowing them to capture more light and offer better dynamic range.

On the other hand, most smartphones often have smaller sensors. These sensors are physically smaller in size, capable of capturing less light than large sensors, that’s why your phone despite its high megapixels offering is not able to compete with high-end cameras.

Log Profiles

Many cameras provide logarithmic (log) recording profiles, such as S-Log, C-Log, or V-Log. These profiles enable capturing a wider dynamic range by distributing tonal information more efficiently across the image. However, using log profiles requires post-processing and color grading to restore proper contrast and color.

RAW vs. Compressed Formats

Recording in a RAW format preserves more dynamic range compared to compressed formats like H.264 or MPEG. RAW files contain unprocessed sensor data, offering greater flexibility in post-production to adjust exposure and recover details. Like log profiles, even RAW requires post-processing and color grading.

Lighting Techniques

Techniques such as using fill lights, reflectors, or diffusers can help balance the contrast between bright and dark areas, allowing for better control over dynamic range during the shoot.

Exposure Techniques

Exposure refers to the amount of light that reaches the camera sensor or film, determining the brightness or darkness of an image. Understanding the exposure triangle, the trio of Aperture, ISO, and Shutter speed, and its relationship to dynamic range is crucial for achieving well-exposed images. Additionally, Exposure aids such as metering and histograms can help ensure proper exposure levels.

Color Grading

The process of color grading in post-production significantly affects the perceived dynamic range of your footage. Adjusting contrast, shadows, highlights, and color balance can further enhance the captured dynamic range and create the desired visual look. The technique is High Dynamic Range (HDR) imaging, which involves merging multiple photos of the same scene taken at different exposures to create an image with a wider range of tones and better detail in shadows and highlights. Exposure blending is another technique that selectively combines different parts of multiple photos with different exposures to create a final image with a wider dynamic range.

Just remember cameras are continuously improving dynamic range by improving their sensor capabilities and image processing algorithmsNew Sensor technology BSI and sensors and tacked CMOS sensors focus on improving dynamic range. Also, image processing DUAL – ISO is an improvement over traditional ISO, which leads to more noise. And then some cameras offer inbuilt HDR modes that combine multiple exposures to provide a wider dynamic range.

As a filmmaker, understanding these elements will help you bring out videos or images with the finest details. Remember, nothing is more powerful than an image that stirs your soul and evokes emotions.