Tone in photography – Shades of grey and exposure in auto mode
Photography is all about capturing the essence of a scene, conveying emotions, and telling stories through images. To achieve this, photographers must master several technical aspects of their camera, such as tone, which plays a crucial role in the overall quality and impact of an image. Tone refers to the brightness and contrast of a photo, and understanding how to manipulate it can transform a good image into a great one.
In this post, we’ll dive deeper into the concept of tone in photography, exploring what it is, how it works, and why it’s so essential for capturing stunning images. From understanding the basics of tone to exploring different camera settings and techniques, this post is the ultimate guide to mastering one of the most fundamental aspects of photography.
How a camera works out black, white and grey
A camera measures how much light is falling on your scene, and this information is used to create an image. The ‘tone’ is the difference between the lightest and darkest areas in a photograph. Every camera programme turns every image to about 18% average grey tone, which is why it can be confusing when the image doesn’t match this expectation.
Not every image is 18% grey, and this can cause confusion for the camera. For example, a black cat in a coal cellar is made up of dark tones, and the camera will overexpose trying to turn it lighter and closer to 18% grey.
On the other hand, a white cat in the snow is made up of light tones, and the camera will underexpose trying to turn it darker and closer to 18% grey. Understanding how the camera interprets tone and the factors that affect it can help you take better photos and avoid common mistakes.
What is ‘tone” in photography
Tone or tonal range has a range of definitions in photography but the use here is to describe the differences between the very darkest part of a photograph and the lightest part of a photograph.
Dark tones are the shadowed areas on a photograph
Light tones are the bright or highlighted areas on a photograph
Our eyes automatically ‘see’ the range of tones in a scene and can distinguish details in very bright and very dark areas. However, the camera doesn’t do this automatically and misses some of the detail at the very edges of the tonal range. The camera struggles to define the tone as it assumes that the average tone of the whole image is 18%.
The overall tone in photographs is the average of all the tones. By turning the image to black and white and then blurring it out, the image you end up with is the overall tone and on auto mode, this will be about 18% grey.
Correct exposure in photography – tone
When you take a photograph in auto mode your camera will measure the amount of light falling on your subject. It will juggle the exposure to make sure that the right amount of light passes through the lens and reaches the sensor.
The camera programme will ensure that the photograph you get is not too dark or too light (a bit of a Goldilocks moment as I write this!!). This is fine for day-to-day snaps, but the camera will get confused once you try to get a little more adventurous.
| Over Exposure | Under Exposure |
|---|---|
| Too much light reaching the sensor | Not enough light reaching the sensor |
| Image too white or bright | Image too dark or black |
The importance of tone in photography is more noticeable when using auto mode and there is little differentiation in tone between objects. It will struggle to capture a black cat in a cellar or a white kitten in the snow as the programme is constantly trying to give the 18% mid-grey average tone. It also won’t want to cooperate if you are trying to get the moody grey sky over a dark landscape or the white butterfly in a field of daisies.
The example below is an arctic tern in black and white against a grey overcast sky.
With the correct exposure, there is a good range of black and white and the details are all really clear. When it is overexposed everything is too white and bright and the details are lost. At the opposite extreme when the image is underexposed it is all too dark and all the light details are lost.
On auto mode, the camera would really struggle to work out where it should be setting the exposure and will attempt to go for a mid-grey average. This means that it may over or under-expose the scene, trying to give the mid-grey tone it is programmed to achieve.
How can I get the correct tone in my photographs?
If you are comfortable shooting on auto mode and don’t want to change then unfortunately you are stuck with an average of about 18% grey on your photographs.
However, it is possible to show the camera who is in charge. By turning your camera off auto you can control how much light reaches the sensor and move away from the mid-grey tones.
You can control the shutter speed, size of the aperture and the ISO which allows you to capture the black cat in the cellar or the white kitten in the snow!
Try it out!
If you don’t believe this happens try this little experiment!
- Put your camera into auto mode and place two pieces of paper – one white and one black into a well-lit area. Make sure there are no shadows, highlights or reflections on the paper.
- Fill the whole of your photo frame with the paper and take a photograph of each sheet. You may be surprised to find that they are both mid-grey!
- You can take this further by placing black objects onto black paper or background and white objects onto white paper or background and see how your camera struggles to get the correct exposure even out on adventures there are moments when this will catch you out!
Want to learn more about photography? Read more on my photography page.
