3. Use low ISO if possible
Although using high ISO usually helps make sense when shooting at night, this also increases the noise in your images. The current high-end cameras are so advanced that they can allow you to take noiseless pictures at high ISO settings, maybe up to ISO 3200 or more. However, cameras with limited light sensitivity range, using a lower ISO is the most practical approach for most consumers.
You should learn the ISO levels limits of your camera by taking some low light shots with different ISO settings. Examine the images to find out at which level of ISO it gets too noisy. For example, if it looks unusable at ISO 1600, stick to settings lower ISO than that.
If your camera can shoot up to ISO 25,000, that doesn’t mean you should use it. It’s safe to keep your ISO low since you’re using a tripod. ISO 400, 800, or even 1600 should be enough in most situations while ISO 100 may be impractical for photography at night.
4. Shoot RAW
For most casual photographers, JPEG is the perfect file format because they don’t take up a lot of space on your memory card. Moreover, JPEG files can be uploaded without being converted into another file. However, when you’re shooting scenes with high dynamic range, this file format makes it problematic due to compressing your image files drastically.
In case of shooting at night, you should switch your image files to RAW in the menu of your camera. Although RAW files take up much space on your memory card and they need to be edited afterward, the quality of your images is preserved.
In order to avoid grainy pictures, RAW file format is the best option because of its low light and post-processing. Even after post-processing, RAW files still maintain their quality. That is unlike JPEG files. After editing your RAW file image, you can convert it to any other format you want, for example, JPEG or PNG.