Thanks for the responses. I figured out the SD-in SD-out thing shortly afterwards. I guess I was a bit optimistic to expect to get more out than I put in. Going component gave me my HD, and it was good.
It's just a shame the BMD product page doesn't make this limitation clearer, the blurb and diagram don't seem to mention it. It's significantly reduced the range of the camera stock I can use with it to give me the HD-SDI I need to input a fly-away kit.
BMD Mini-Converters Product Blurb wrote:Perfect for converting from analog HD/SD component, NTSC, PAL or S-Video to SDI out with balanced jack AES/EBU and analog audio embedding. Now you can convert analog devices such as Betacam SP, VHS, set top boxes, gaming consoles and HDV cameras to incredible quality SD/HD-SDI video.