Copyright only prohibits certain kinds of publication of derivative works.

You are free to make as many photos of an object (or objet d'art or artwork including a painting or even another photographer's photos) as you like, but not necessarily free to publish it wherever you like.

A work such as a photograph is copyright the instant it is created, which is when the shutter is clicked. That includes any derivative works made by the same author from it, such as scans or files or prints or silver gelatin prints, etc.