In this video tutorial by PhotographersOnUtube, I learnt about all the basic functions and settings of the flash gun ; difference between manual and automatic(ettl) mode, zoom function which used to match whatever focal length the camera is shooting in, and finally the different angles of the flash head.
The zoom on the flash can also be set manually or automatically, and should ideally follow the focal length of the lens in order focus the light correctly, for example if shooting with a telephoto lens with the subject further away, the zoom on the flash should also be set to focus the light further into the distance in order to illuminate the subject properly.
This video also shows the different effects produced by different angles of the flash head. Shooting a portrait of his subject, he starts from pointing the flash directly at his subject, then at an angle of 45Degree, then 60, 75, and finally 90(pointing directly upwards). This clear comparison gave me a much better understanding of the function of flashing and different angles.
zenkhyeooi 