Why use Manual mode?

Manual mode (M) gives you direct control over the three main exposure settings:
- Aperture: Controls how much light enters the camera and affects depth of field.
- Shutter speed: Controls how long the camera sensor is exposed to light and how movement appears.
- ISO: Controls how strongly the camera amplifies the image signal. Higher ISO values produce a brighter image but may increase digital noise.
In Manual mode, the camera does not automatically adjust the aperture or shutter speed to correct the exposure. You must select and evaluate each setting.
Shutter speed
Shutter speed controls how long the camera sensor is exposed to light.
- A fast shutter speed records a brief moment, freezes movement, and allows less light to reach the sensor.
- A slow shutter speed records movement over a longer period, creates motion blur, and allows more light to reach the sensor.
Shutter speed is written as a fraction of a second:
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
A larger denominator represents a faster shutter speed. For example:
1/1000is faster than1/30.1/1000exposes the sensor for less time.1/30exposes the sensor for more time.
Shutter speed in Manual mode
Because the camera is in Manual mode, it will not automatically compensate as the shutter speed changes.
As a result:
- Faster shutter speeds will generally produce darker photographs.
- Slower shutter speeds will generally produce brighter photographs.
- The appearance of movement will change from frozen action to visible motion blur.
This activity demonstrates how shutter speed affects both movement and exposure.
Use the histogram
In Manual mode, the camera does not automatically correct the exposure. The histogram provides a visual record of how the selected aperture, shutter speed, and ISO affect the distribution of tones in the photograph.

Use the histogram to evaluate the image after each exposure:
- The left side represents shadows and darker tones.
- The middle represents midtones.
- The right side represents highlights and brighter tones.
- A graph pressed against the left edge may indicate blocked shadows with little or no visible detail.
- A graph pressed against the right edge may indicate clipped highlights with lost detail.
The histogram does not need to be centred. Its shape depends on the subject, background, lighting, and intended visual result. A dark scene may naturally contain more information on the left, while a bright scene may contain more information on the right.
Subject movement and camera movement
Motion blur can come from:
- Subject movement: The subject moves while the camera remains stationary. This requires a tripod.
- Camera movement: The camera moves while the shutter is open.
- Both: The subject and camera move during the exposure.