Conventions of music videos

The conventions of music videos tend to vary between different genres and even between artists (to an extent). As well as there being 'set' conventions, there are also 3 main types of music videos: narrative video, concept based video and the performance video.

Although you often see the artist performing in the majority of videos, the performance video will mainly focus on the artist performing the song to a crowd, or to no one in particular. This is a very common video format in the rap, indie and rock genres and a lot of what makes the artist popular is their image and relationship with their fans.
The concept video is also very popular with the rock and alternative genre, often due to the nature of the lyrics. One example of a concept based video is 'crazy' by Gnarls Barkley. This video uses the Rorschach test as the concept, with each inkblot becoming the lead singers face. The use of the Rorschach test coincides with the title and lyrics, as the test uses inkblots to determine somebodies personality and whether they may or may not be insane,
The third (and probably the most common) type of music video is the narrative video. This video will tell the story of a character, often using the lyrics as a guide to what will happen to the characters in the video. One of the most famous uses of this could be 'Stan' by Eminem. The song itself outlines the messages of a highly obsessive fan who eventually commits suicide. The video consists of this fan writing the messages to Eminem, and getting increasingly frustrated when his letters are not returned. Anyone who has heard the song before viewing the video would most likely have some idea to how the video ends. Unlike performance and concept style videos, the narrative seems to be spread evenly throughout the various genres of music, as a lot of songs are about events rather than an idea.

There are also conventions in terms of camera work in the music video industry. Once again, these are mainly spread out throughout the genres of music, and often coincide with the type of video being filmed. The colours, characters and locations used are yet another form of convention used in the music video industry.
Close ups can be very common within music videos as they suggest a sense of intimacy, either between the characters, or even between the band and the viewer. Medium shots tend to dominate the music videos as  this way, most of the band is fitted to the shot, ideal for performance videos.

Depending on the song, music videos tend to be slightly longer on both ends of the song, especially in narrative videos, as it is essentially a short film, giving time for the characters to be introduced. One example of this could be 'The kill' by 30 Seconds To Mars. This video pays homage to the Shining, and there is both an introduction and an ending to the video. There are also short breaks in the song to allow for the story to unfold, unrestrained by the  songs length. This can be very common among some artists (30 seconds to mars have done this plenty of times in their music videos) therefore some artists often have their own conventions set out.