By default, regardless what/how you want to send images from a PC or Mac (HDMI), HDCP is added as the VC-1 is recognized as an HDCP compliant device - resulting in nothing being sent to the SDI output.
If you know that the material is not HDCP based then here is what to do to get it out the SDI:
- Connect the unit via USB to your computer and run the VC-1 RSC (Remote control software available in the download section of the product page). Make sure dip switch #10 on the side of the unit is ON so it becomes controllable by the software.
- Then set the "Input HDCP Key Mask" field to "ON". This way the HDMI input will be recognized as "Not HDCP". The image should pass thru to SDI no problem.
Please also note that even with the Input Mask set to ON, if you truly have protected content coming through, it still will not play out the SDI port.