Posters designs depend a lot on their subject matter, and how much information needs to be on them. Inspirational posters, for example, need only have only one word on them, (ie the classic “Conviction” or “Perseverance” posters that hung on the walls of every guidance counselor office from 1960 til today), while tour or movie posters need to have names, dates, times, taglines, and prices on them as well as the title in order to be useful. The more elements to a design, the harder it gets for the poster to be easy to read and arresting. Here are some examples of poster design by genre, and how designers have solved the problem of necessarily text-heavy posters.
Music posters are usually lighter on text and feature the names of only one or two bands, meant to be sold specially as collector’s items. This leaves a lot of room for the non-textual elements to take more of center-stage because the poster is created with more aesthetics instead of informational use in mind; for example the posters for The Glitch Mob, Battles, and Girl talk are supposed to go on someone’s wall instead of catch the eye of passersby on the street. Even if they are designed to be street posters like the Dinosaur Jr. or Gorillaz ones, sometimes it pays to sacrifice readability for design because it goes with the aesthetics of the show so much that you can be fairly sure fans interested in going will take the time to read it. The Black Crowes’ poster has hard-to-read text but it works with the design; being careful with space and balance is key.
These posters have to clearly show the names of the actors, directors, producers, and film studios involved, as well as when it premiers and also possible reviews. With that much information to cover, its no wonder that many movie posters have arresting images but relatively simple text that lines the bottom like in the Dark Knight or 50ft. Woman movie posters. Although typography is great, sometimes simple is best.
PSAs usually have only one message, along with tags for further contact or information like a website. Because of this, they are not often busy with text and images all over the place but rather feature one arresting image, and the information laid out in simple typography. The Bullying and Haiti Relief posters have a lot of copy, so it makes sense that the images and color scheme would take a back burner to that. Here, information is more important than visual stimulation.
For each genre of poster, knowing your audience and the objectives of the poster is key. The balancing act between copy and art is sometimes tricky, but I think at the end of the day a good rule of thumb is simplicity; sometimes the most stark combination gains the most notice.