Saw Poster's Analysis

Here are the 1st four teaser posters of the 1st four 'Saw' films. All four of them follow the same theme of having a white background and using human body parts as the main feature of the poster. This making the audience look but feel horrified which is what the poster aims because of what the films are about.
The 1st poster is the only one that shows the audience some of the actors that are featured in this film. I think this is because it was the first saw film so they had to attract their audience. Whereas, with the other pictures they just have to mention the name of the film and they would still attract their audience.

On all three posters, once again they don't have that much large information given that could distract the audience from the main feature of the poster. They mainly only have the title in a large font and a large image so that the audience can't miss it.
 I think they used this so that the audience understand that the killer character in these films is mentally ill and is very sadistic.