A good poster isn't a busy collage — it's one clear idea that still reads when it's shrunk to a thumbnail in a feed. Three things carry most of the result, and the generator is tuned around them.
Genre sets the look. The fastest way to signal what a film is is color and light. Horror leans cold, high-contrast, and shadow-heavy; action runs warm orange-and-teal with hard rim lighting; indie drama goes muted and grainy with lots of negative space; fantasy goes wide and luminous. Picking a genre preset loads that whole visual grammar at once instead of you tuning it by hand.
Composition that reads at a glance. Strong posters use a clear focal point and the rule of thirds — a centered hero or a single striking image, not five competing ones. The generator keeps one subject dominant and leaves the top or bottom third open for the title, the way studio one-sheets do.
Best photo for photo-to-poster. For the image-to-image styles, the input does a lot of the work. A clear, front-facing portrait with even light and an unobstructed face holds your identity through the restyle. Sunglasses, heavy filters, hard shadows, or a tiny low-res face give the model less to anchor to, so the likeness drifts. One sharp, well-lit photo beats a busy group shot.