Most music videos are conventional according to genre, e.g a rock video would be conventional to the rock music genre, and an r'n'b video to the r'n'b genre. However, there are some conventions to a music video which apply to every genre (in most cases).
Most widely, a music video will be based around (or will refer to briefly at least) the artist of the song. For example, in a rock music video, although there may be a linear storyline there would usually be clips of the band playing alongside it. In the example by 'My Chemical Romance' pictured below this is made evident - although all scenes appear to be in the same location, the video flits between a funeral scene with dancers and images of the band (mainly frontman Gerard Way) performing the song.
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My Chemical Romance - Helena |
Most importantly to a music video, particularly pop, is changes in location and costume which ensures that the video keeps the viewers attention and avoids fatigue. This is really, really important to a music video because at the end of the day, the video is made as a promotional tool to sell the record, so if the viewer finds it boring they're a lot less likely to want to buy it and a lot more likely to just change the channel.
Using location can also set the scene for a video and genre, for example in the My Chemical Romance 'Helena' video (pictured left), the dark, funeral church location is conventional to the band's emo rock genre and thus appeals to their target audience of teenagers, especially those who engage in the 'emo' style cult. However, this type of setting is a lot less likely to appear in a pop or an r'n'b video as it is unconventional to the genre. A consistent change in location and setting is very typical of a music video as well as avoiding viewer fatigue.
Costume is paramount to a music video, costume helps to define an artist as a media personality and within their genre. An example is Lady Gaga (pictured below) who has used bold fashion statements to make herself a household name worldwide and sell her music by creating a fanbase around her flambouyant character as well as causing quite a bit of controversy along the way. Using costume as a tool not only allows an artist to 'express themselves' but also avoid viewer fatigue and create a fanbase around their use of fashion, which is also evident from Florence Welch who has become a fashion icon.
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Lady Gaga and infamously controversial 'meat dress' |
Use of cinematography and lighting is the final fully transferable convention of a music video. Pop videos often use a lot close ups of the artist's face to introduce them to the viewer and often a lot of bright lighting is used, normally as a tool to flatter the artist as the artist's look is key to sales. As well as a lot of close-ups music videos use a lot of long shots, in rock music videos this is often to show the whole band within the frame and in pop or r'n'b to show the artist's (or dancer's) bodies as they're often performing dance moves. and need to show their costumes.
In terms of editing shot rotation tends to be fast and fluent in all music videos of all genres mainly to avoid viewer fatigue. However, in general editing is pretty standard for music videos and quite basic, usually a mix of a narrative structure with the occasional performance based shot.