**System Information**
Linux Mint 15, GTX 650
**Blender Version**
Broken: 2.70.3 36defb7
**Short description of error**
The backdrop in the compositor (and Image Editor set to Viewer Node) shows black pixels instead of transparent ones when the image has alpha information.
**Exact steps for others to reproduce the error**
(BI is "harder" to setup for this)
# With Cycles, Film set to "Transparent", do a render of the default cube.
# Switch to the node editor, activate "Use Node" & "Backdrop"
# ctrl-click on the render to get a viewer node -> transparency is ignored, while present in the node(s) preview(s)
**Screenshot**
{F85329}