Flash refers to an artificial source of super strong light that is used for bringing more light to photos when needed. The firing of the flash is just before you shoot the photos so that there will be more light for the lens as well as image sensor to capture a digital image. Flash can be known as either the flash of light during image capturing or the physical flash unit which produces the light.
You will often find a built-in flash unit in cameras that are aimed at entry-level photographers and the firing of the flash is commonly automatic whenever there is a need for more light. The flahs configurations can be changed through the menus of digital models and you can also fully turn of the flash. But when you use these available small flash units on entry-level models, you possibly encounter a redeye issue with your images.
For high-end digital models, you can control the flash better, both the flash firing and the amount of the light from the flash. The sizes of these flash units are often larger and they are stronger. In addition, you are able to remove the flash from high-end cameras.
A powerful flash of high quality will be very useful for making the image quality better while for some other tiny built-in flashes, the range for working well may be just several feet, for instance.
When the autofocus function is being used and the camera needs addition light from the flash, there may be at least two flashes. The first one is to bring more light for the camera to make use of the autofocus feature while the second one refers to the actual flash for shooting the photo.
The word “flash” can be also known as the flash memory, even though these two things of a digital model has no relation.