Three actual built-in image_gen outputs of one fictional subject — generative edits, with texture and tone drift, rather than a measured physical lighting test
Rembrandt request
Small illuminated patch below the camera-right eye bounded by nose and cheek shadow
Loop edit request
Broader camera-right cheek illumination and a shorter nose shadow, with no isolated triangle
More fill request
The shadow-side cheek becomes brighter and the triangle is less distinct
The loop and fill variations each reference the original base. Cover artwork is a separate edit. Diagram coordinates are an authored planning suggestion.