WHEN TO, AND WHEN NOT TO USE FLASH
First of all, there are some situations where using a flash is pointless and unnecessary — knowing when not to use it will allow you to save time on trying out each setting one by one. Flash seldom works well in big events because it will only have an effective range of about 3-5 metres. Additionally, us flash for concerts, as it may cast shadows and distract the performers on stage. A simple alternative to this is to open the aperture and raise the ISO, enabling you to take well-exposed photos in low-light conditions, while still preserving each organic moment. You could also consider putting your camera in a priority mode and adjust each setting properly.
The most popular usage of the flash is in dim lighting. Be it indoors or at night time, the flash will illuminate your subject when there is insufficient natural or ambient light, allowing you to define all the important details clearly. Doing this will prevent motion blur resulting from slow shutter speeds and excessive noise in your photos due to an ISO level that is set too high, leaving little room for post-processing.
While shooting, you can also get creative even with the flash turned on. In night photography, it can be used for long exposures, light trails or even freezing the light in certain parts of the frame. These effects dramatise your overall composition and elevate your art.