A Good way to publish Photos copyleft

I am looking for a good way to publish images as copyleft. The current state of the art in licensing non-software seems to be creative commons, but its copyleft is so weak, that I don’t see how it protects the end users’ freedom. To be more precise, here is how I perceive the legal effects (please correct me if I am wrong):

· I publish a digital picture in high resolution, with intermediate files under CC-by-sa
· Magazine XY takes the picture, touches it up and prints it as part of some article in a small size
· user Z sees the picture in the article and doesn’t even know the associated rights, unless she looks in the table of figures; and even if she does she can only demand the ready-to-print down-scaled version of the photo, possibly with text covering it, in a non editable format

→ what’s the point? Where is the freedom? What do I gain as an author, if I let commercial magazines use my photos, that in turn, don’t share with my fellow citizens?

Why do we not treat pictures like software? Obviously there is a preferred way of making changes, which might be a format with layer and effects information, or even a non-destrucitve instruction set, like with darktable. This is != to the preferred form of distribution, which is some form of bitmap, so it makes sense to speak of source and non source in my opinion.

I want to release my photos in a way that forces people to make the source of my photos as well as the source of their changes available to all third parties. So I thought about just stuffing the original image, with intermediate formats and/or instructions in a tarball, add a GPLv3 file and a note, on how I define that the GPL applies. Does that make sense? Or have you come over other, easier ways to achieve a similar effect?