Negative prompt

A negative prompt is the opposite of a regular prompt. Where the prompt describes what should be in the image, the negative prompt lists things the model should steer away from. In diffusion models it works by pushing each denoising step away from those concepts. It is most useful when a result keeps adding something unwanted, such as cars on a pedestrian street, text on a facade or a dramatic sky on a scheme that needs calm light. Not every tool exposes a separate negative prompt field.

In practice

• Keep it short and specific. A few targeted words work better than a long list of everything that might go wrong.
• Use it to fix a recurring problem, not as a default. If the image is fine, a negative prompt adds nothing.
• Write it as plain nouns: "people, cars, signage", not sentences or "no people".
• Check whether the regular prompt is causing the issue. Words like "busy street" invite the very crowds you are trying to remove.
• If one unwanted object remains, editing it out of the finished image is often faster than rerunning.

In Rendair

For a specific unwanted element in a result, Remove Object takes it out of the image directly, and Conversational Edit lets you describe a change in plain words. See diffusion model for why models add things you did not ask for.