Use one master prompt (change only [PRODUCT] and --seed):
Product shot of [PRODUCT], studio seamless white background, single softbox key light 45° left, fill reflector right, subtle rim light, neutral white balance, realistic soft shadows, 50mm lens f/8, 45° camera angle, consistent scale, true-to-color detail --ar 4:5 --v 5 --q 2 --seed 12345
Negative tokens: --no people --no props --no text --no watermarks --no color shifts --no harsh shadows --no perspective distortion
Run identical prompt + seed for every SKU.
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