User blog comment:Semanticdrifter/The CC-BY-SA License and You/@comment-954127-20120717222227/@comment-65179-20120718190122

Speaking as a graphic designer, and while not an expert in the feild, I am at least familiar with graphic design.

When it comes to collages you cannot license them as CC-BY-SA unless you produce them only with images you own the license to. Because this license gives others the right to re-work your work, you've basically released another artists work into the CC, and that's just not right. That's theft.

Because the CC-BY-SA license incurs rights on the collage, you can only make them using your own work (or works already in the CC). In short: If you didn't create every part of the image yourself, you have no freedom to release it into the CC.