When I take a photo of a real world sculpture and say 'I have made this picture', everybody understands that I talk about making the photo (an Art) and not about making the sculpture ( an other Art). If I talk about a render of a digital sculpture (the model), this distinction may be not as clear to most people. So a bit more explanation may be necessary. That has nothing to do with the fact that both making the render and making the model can be art.