The right ISO for your shot depends on the lighting where you are taking your pictures. To learn more of what ISO is visit “What is ISO?” Ideally you would want to have your ISO set to 100. There are plenty of low light scenarios that make it prudent to change the ISO.
Since you want the sharpest photos possible the ISO is a setting to keep an eye on. Remember that the higher you set the ISO the lower light your camera can handle, however that higher ISO will also increase the amount of visible noise or graininess also. You want to find a balance between how dark it is and how much noise you can get away with in your photos without it ruining the shots. Take the time to take a few test shots before settling with your preferred ISO setting.
Also be sure to have a tripod available when you are going to be in low light settings to be sure to minimize the movement involved that would possibly make it grainier. You will want to do everything you can to make it sharp, even when you have to raise the ISO.
Suggestions for ISO in Various Scenarios:
- Fireworks: 100 (do not change)
- Dusk: 200 to 400
- Stars: 800 to 1600
- Sunsets/Sunrises: 200
- Evening Parties: 800
- Stormy Weather: 400