I once found a paper craft DIY-ring-flash-adaptor online, which redirects the light coming from a normal camera mounted flash and spreds it evenly around the lens of the camera. I thought this should be possible to achieve with a 3d print.. so here it is. Glue the 2 parts together and glue in some aluminum foil for reflectiveness. Here is a papercraft version I found as reference: http://templartan.blogspot.de/2009/03/my-diy-project-ring-flash-adaptor.html This will probably not fit for every flash and I can't even say if it fits my flash since my printer is ordered but still in the making. But maybe it's an inspiration for you experienced modelers out there to create a working one for your camera-flash-combination. Or modify this one... leave a comment if you want the blender file for this.