Many conventions of a music video changes with each genre however there are also a lot that are widely spread over every genre. A music video does not have to contain every convention, in fact many successful ones only follow a few and create their own ideas making them stand out from the rest. Although almost all music videos follow the basic guidelines to making a successful, professional looking music video.
One of the main things a lot of music videos do is to not have the same things throughout. For instance change the location and the costumes a number of times. The location and costume changes often link to different parts of the song and the lyrics as most things in the video need to have a relationship with the lyrics and the meaning of the song. For example if the video is narrative based the costume and location will follow the story. Many artist are well known for costume changes especially Lady GaGa and to a lesser extent Katy Perry.
These changes to the location and costume help to reduce viewer fatigue as it makes the music video feel exciting, easy to remember, and interesting.
The editing of the music video is also very important as it helps set the overall feel to it. If the editing is fast paced with quick cuts you would assume that this mirrors the song and would make the video feel exciting and upbeat. On the other hand if the cuts are slow and each clip is fairly long then you would assume the song is slow, emotional, or meant to feel calm. The editing stage is also important because of the lip syncing. If the lip syncing is not in time or incorrect at all it will be easily noticed and the viewer would feel cheated and not believe that the artist is really singing it like they are meant to believe.
I think music videos many videos follow the convention that they do not tell the whole story but leave it slightly untold. The ambiguousness of this allows the viewer to take the songs and shape it to a situation in there own life and think that they relate to it.
Camera angles and movement is also a big deal in music videos. The main convention is that the shot type changes continuously to give the viewer something new to look at to avoid viewer fatigue. The camera should also move a lot, e.g. pan and tracking.
Although these are what most successful music videos contain the genre of the song/artist often changes what the video should be.
Rock:
Rock music videos tend to have dull or limited lighting and dark locations which often link in with the lyrics to the song. As rock songs tend to be fast the editing of the video is also is fast paced and exciting. I found that rock music videos mainly seem to have an on going narrative that cuts back and forth to the band playing the song live, showing close ups of each band member. For example in 30 Seconds To Mars - Kings and Queens the band is shown at the front of the bike ride and then cuts to them playing the song live on a roof top.
Pop:
Pop music videos tend to be very different to rock as the lighting is often bright while the colour bold and bright. Instead of showing bands playing I found that pop videos usually cut to dancers alongside a narrative. One of these dancers was the main artist who was always in the centre of the frame. For example in Lady GaGa - Poker Face, the artist is shown in the centre of the frame most of the time while cutting from narratives, to group dancing, to solo dancing.