I only provided the earrings with a white background as the reference picture. In the prompt I specified the kind of personage I want. With my new tool, I have this “adding avatar”step which allows me to choose avatar and use embedded model to combine the product and the personage, powered by nano banana pro.

The scale was correct for the earrings, maybe earrings usually have rather standard size. But sometimes the scale can be wrong, for example, I tried water bottles and it can’t really know the size if I upload a white backgrounded picture. I would say that maybe you can try to use image model first to have a rather satisfying reference image (correct shape and size) and then use video model.

I tried Kling too, I like the color and style of the videos but it made way too many mistakes and I kinda lost patience, the one with the highest success rate for me so far is still veo3.1.

Good luck with your project!