Lesson Content

The –ar parameter.

The --ar (aspect ratio) parameter specifies the width-to-height ratio of the generated image. Format: --ar width:height (e.g., --ar 16:9 for widescreen, --ar 9:16 for vertical video/portrait, --ar 1:1 for square, --ar 4:3 for standard). This parameter is added to the end of the prompt, after all descriptive text.

Matching aspect ratio to use case.

Common use cases: --ar 1:1 for square social media posts; --ar 9:16 for Instagram Stories, TikTok, YouTube Shorts (vertical); --ar 16:9 for YouTube thumbnails, presentations, landscape; --ar 4:5 for Instagram portrait feed posts; --ar 3:2 for standard photography; --ar 21:9 for cinematic widescreen. Always set the aspect ratio before generating production images to avoid cropping or padding issues in downstream use.

Aspect ratio and composition.

The aspect ratio chosen affects the composition generated – a square image composes differently than a widescreen image for the same subject. Include framing guidance in the prompt that works with the intended aspect ratio: "portrait framing, vertical composition" for 9:16; "wide establishing shot, horizontal composition" for 16:9.

Pan and Zoom for dimension extension.

Pan (extend the canvas in a direction) and Zoom Out (expand the view outward) functions extend image dimensions beyond the original generation – useful for creating wider compositions from a good image base without full regeneration. Available on upscaled images through the interface controls.