Lighting Prompts: From Hard Shadow to Soft Fill, the Vocabulary I Actually Use
Lighting vocabulary changes outputs more than any other prompt category. Here are the descriptors I reach for and why each one earns its place. Lighting is the prompt category that most reliably moves an image from flat to dimensional, and it is the category I see most under-specified in prompts from new users. A subject described in detail but with no lighting instructions renders under what amounts to a default ambient wash, which flattens form and kills mood. Describe the same subject with explicit lighting and the same model sculpts the form with shadow and highlight. In this guide I will lay out the lighting vocabulary I actually use, grouped by the problem each term solves. The Three Decision Points Every lighting description I write covers three things: the direction the light comes from, the quality of the light (hard or soft), and the color temperature of the light. Direction controls where shadows fall and how form reads. Quality controls how sharply the shadow edges transition. Temperature controls mood. Skipping any of these leaves the model guessing, and the model guess is usually the most boring possible answer. I write each decision into the prompt as a short clause, not a single adjective. "Soft north-facing window light from the left, warm white, gentle falloff" beats "soft light" because it commits to all three decisions. The longer clause costs nothing and gives the model a real lighting setup to render.