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PostersBy Prompt TemplateVerified on GPT Image 2 / Nano Banana

A poster needs a hero and a spelled headline

Posters collapse into moodboards when the subject is vague and the title is not quoted. Lock one hero, one headline string, and “single poster only.”

2026/09/01

“Make a launch poster” is how you get a presentation board: six thumbnails, a color palette strip, and a title the model invented. GPT Image 2 is good at type. That is exactly why it will write a slogan you never approved.

What actually breaks

We asked for “a poster for Prompt Template.” Round one was a moodboard. Round two, we added a headline but did not quote it; both models produced PROMPT TEMPLETE and a second line AI Art Made Easy. Close, and unusable. Round three quoted the strings and said single finished poster, no grid, no mockups. That is the version we kept.

Sports and type-driven posters fail in two extra ways: collage (racket, shoe, and athlete fighting for the frame) and lettering that does not touch the subject. If the figure sits next to the word instead of through it, you have a stock photo with a caption.

The rule we use

  1. Name the hero. Person, object, or letterforms — pick one. “A poster” is not a hero.
  2. Quote the headline and subhead. Spelling is a constraint, not a vibe.
  3. One poster. Ban moodboards, process sheets, and “six options.”
  4. Type interacts with the image. Overlap, crop, or eclipse — not a sticker on top.

Nature-science posters want the animal huge (half the frame) and four short facts, not a textbook.

Example we actually ran

Weak

A cool launch poster for our prompt template product, typography, cinematic.

Locked

Single 4:5 editorial poster, no moodboard, no mockup, no color-palette strip.
Hero: a hand turning a physical color-swatch wheel in front of a dim computer.
Headline, spelled exactly: "PROMPT TEMPLATE"
Subhead, spelled exactly: "Every variable is a control."
No other large text. Restricted palette: ink black, paper ivory, signal blue #2563EB.
The headline is the largest object; the hand overlaps the letters P and T.

GPT Image 2 honored the spelling when the quotes sat above the style words. Nano Banana needed do not add extra slogans at the end. Without it, Tweak it. Copy it. Ship it. showed up uninvited — our tagline, but not this poster’s copy.

When to open this guide from a control

Change headline and hero independently. If you only swap the hero and leave headline as “something catchy,” the model will brand the new subject with a new slogan. That is a different poster, not a variant.

Sources

Rewritten from public pitfall notes; the swatch-wheel launch poster is ours.

Controls this guide covers

  • headline

    Hard-code the headline spelling. Otherwise the model improvises a slogan.

  • subhead

    Give the subhead as a quoted string, or it will compete with the title.

  • hero

    Say what the hero actually is. “Make a poster” leaves the subject to chance.

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