The "good" ISO depends entirely on the amount of light available and the effect you're trying to achieve. There isn't a single universally "good" ISO value.
In photography, ISO refers to the sensitivity of your camera's sensor to light. A lower ISO means less sensitivity (better for bright conditions), while a higher ISO means more sensitivity (better for low-light situations). However, increasing ISO also increases the amount of noise (graininess) in your image.
Here's a general guideline:
ISO Recommendations Based on Lighting Conditions
| Lighting Condition | Recommended ISO | Notes |
|---|---|---|
| Sunny Day/Bright Outdoors | 100-200 | Aim for the lowest ISO possible to minimize noise and maximize image quality. |
| Cloudy Day/Overcast Outdoors | 400 | Allows for faster shutter speeds to avoid motion blur, even with slightly reduced light. |
| Indoors (Well-Lit) | 400-800 | If you're near a large window or have good overhead lighting, these ISOs should work well. |
| Indoors (Low Light, No Flash) | 800-1600+ | Be prepared for some noise, but this will allow you to capture images without a flash. Experiment to find the highest usable ISO for your camera. |
| Very Low Light (e.g., Night) | 1600+ | Expect significant noise. Use only when absolutely necessary and consider noise reduction techniques in post-processing. A tripod is highly recommended at night. |
Understanding the Trade-Offs
Choosing the right ISO is about balancing light sensitivity with image quality.
- Lower ISO (e.g., 100, 200): Less noise, but requires more light or longer exposure times (increasing the risk of motion blur).
- Higher ISO (e.g., 1600, 3200+): More sensitive to light, allowing for faster shutter speeds in low-light situations, but introduces more noise.
Tips for Choosing the Right ISO
- Start with the lowest possible ISO: Gradually increase the ISO only if you can't get a properly exposed image with your desired aperture and shutter speed.
- Use a tripod: A tripod allows you to use slower shutter speeds in low light, enabling you to keep the ISO lower and minimize noise.
- Learn your camera's limitations: Every camera handles high ISO noise differently. Experiment to find the highest ISO you can use without unacceptable levels of noise.
- Consider post-processing noise reduction: Software like Adobe Lightroom and Capture One can help reduce noise in your images, allowing you to use slightly higher ISO settings when necessary.
Ultimately, the "good" ISO is the one that allows you to capture a well-exposed image with an acceptable level of noise for your specific needs.
