Thanks to Dawson Harvey for the Camera tip!. I also found out that you can actually change the raster level canvas size separately and match it to the camera size if needed to, I assume this is to be able to mimic what would happen as if one was working with papers of different size than the camera frame can register.
If you select the column raster level in the schematic you can access to the Level Canvas Size by going to Files > Canvas Size, however It seems that if you select a frame in the Xsheet this option becomes disabled and clicking again on the schematic node doesn't make it work, this is apparently a widget focus issue, BUT if you hover your mouse on the Xsheet and navigate the frames using the arrow keys the Canvas Size option for the raster level becomes available again. So you can effectively change both Camera and Raster level sizes!
It's a bit weird but it works (thankfully) :)