Each new generation of cameras brings improvements to ISO sensitivity, making it important to stay up-to-date. But first, what exactly is ISO speed?
What is ISO speed?
ISO stands for the International Organization for Standardization. This organization sets the standards that ensure consistency across different films, allowing photographers to make informed decisions about shutter speed and aperture settings.
In digital cameras, ISO is an index that measures the sensitivity of your camera sensor. Lower ISO numbers require more light for a proper exposure, while higher ISO numbers enable you to capture images in low-light conditions by increasing the camera’s light sensitivity.
Why should you care about ISO speed?
Setting your ISO speed too high can result in noisy photos. While this can create a nostalgic effect in film photography, digital noise is generally unwanted as it distorts colors, especially in darker areas.
Let’s compare two photos to understand the impact of ISO sensitivity. The first photo was taken at ISO 12,800, while the second was taken at ISO 80.
As you can see, the blue and purple spots in the high ISO photo are noise that detracts from the overall image quality.
Set the ISO speed to the lowest possible level
To avoid noise, it’s best to shoot with the lowest ISO speed possible. Many landscape photographers opt for ISO 50 for smooth photos. Cameras like the Canon EOS 5D series enable you to set ISO as low as 50, perfect for capturing stunning outdoor shots like the one below:
Machermo and the Moon – Nepal Himalaya – Canon 5D ISO 50
What if a low ISO speed cannot be used?
In situations where shooting at a low ISO speed is not possible, such as in dimly lit auditoriums or stages, what is the appropriate ISO speed setting? Let’s take a look at an example:
In these cases, it’s crucial to know the maximum ISO allowed by your camera. Understanding the noise level corresponding to each ISO sensitivity level helps make informed decisions, especially when capturing memories and emotions outweigh the importance of a perfectly smooth photo.
A simple test
Here’s a straightforward test to determine the maximum ISO level that your camera can handle without excessive noise. All you need are a camera, a table or tripod for stability, dark or black objects as subjects, and sufficient light.
- Securely place your camera on a table or tripod to avoid blurry images at low shutter speeds.
- Select appropriate objects with a dull surface that are dark in color.
- Ensure adequate lighting.
- Set your camera to Program mode.
- Disable noise reduction settings, if applicable.
- Start with ISO 100 (or L if available) and capture a photo.
- Increase the ISO level by doubling the previous setting and capture subsequent photos.
- Continue this process until reaching the maximum ISO threshold of your camera.
Check the result
Download the captured photos to your computer and view them closely. Since you used Program mode, the exposure between photos should be consistent. Avoid enabling automatic noise reduction options in photo editing software like Lightroom for accurate analysis.
In higher ISO photos, you’ll notice more blue and violet noise. Choose the image with an acceptable noise level that suits your preferences. This way, you’ll know the maximum ISO level you can set without compromising image quality.
Some other examples
To further understand excessive noise, let’s explore additional photos that might have too much noise. These examples will serve as reference points when determining the ISO speed limit for your camera.
Remember, finding the ideal ISO setting for your camera involves considering the balance between capturing sufficient light and minimizing noise. By following the steps outlined in this article, you’ll be able to determine the maximum light sensitivity your camera can handle without compromising image quality.