Types of Flash
2- External Flash or hot-shoe
External flash units are those that are purchased separately from the camera but need to be connected to the camera in some way to synchronize with it.
There are a variety of makes and models and to purchase a brand and model that is compatible with the type of camera you are using.
If, for example, have a Nikon have to buy a Nikon flash for our camera model or any alternative brand that manufactures flash for that camera model (eg Metz).
There are different ways to connect the flash to the camera.
I can mount it above the next shoe connection on cameras (it is a square that is above DSRL SLR cameras and provides electrical connection between the flash and the camera), I can connect a sync cable (cable PC ), or I can use an infrared or radio device to trigger the flash.
On the lower photo can see a flash mounted on top of the chamber.
An advantage of this flash is that they have more power than the flash incorporated.
This will allow them to take pictures at greater distances from the object. With the flash, when we are away, the pictures come out dark. This happens because the flash has very low power.
Another advantage of this flash is that most have a head that can rotate vertically and / or horizontally.
This allows us to bounce or reflect the flash on a wall or ceiling to achieve a softer, diffused light.
External flash units do not always have to be used above the camera in the shoe.
As mentioned above, can be placed on a tripod and the camera connected to PC using a cable or an infrared or radio.
There are even what are called brackets where you put the flash and the camera together and connected with a sync cable.
Removing the camera flash can achieve pictures with various lighting and weather. If we leave it always on top of the camera the photos will all be a light in front and flat.
There are also accessories that can be used to achieve a diffuse light (see accessories). A brand that builds these accessories is Lumiquest.