Text-to-image is a great party trick, but the moment you need the same object to appear consistently across a campaign, you need image-to-image. Upload a single clean product shot and you can re-render it in a winter scene, a summer scene, and a studio scene — with the product itself staying pixel-faithful.
Start with a clean reference
The model preserves what's unambiguous. Use a reference with a clear silhouette, even lighting, and no background clutter. A busy reference forces the model to guess which parts matter, and it will guess wrong at the worst moment.
Describe the change, not the object
The most common mistake is re-describing the product in the prompt. Don't — the reference already carries that. Instead, describe only what should change: "the same bottle on wet sand at dawn, soft fog, cool blue light". Every token you spend re-describing the bottle is a token that can drift its details.
Iterate in small passes
Resist the urge to change five things at once. Change the setting, review, then change the light, review. Small passes keep the identity locked and make it obvious which edit introduced a problem.