With an iMac your only options are the AJA I/O (SD only) and AJA I/O HD (HD and SD)…as they connect via firewire. Or, if you are working with DV, simply routing the signal through a camera or converter box (Canopus) will do the trick.
The problem is that the I/Os require the firewire bus be relegated to them and them alone. This means that you cannot connect any media drives to your system. And since you cannot connect the media drives and the I/O…you can’t really use these to monitor anything.
An iMac is a consumer computer…not meant for professional I/O. You can use it to edit easily enough…I know places with several editors on iMacs, but they always have 1 or more professional rigs with capture cards. MacPros in fully setup edit bays. Those bays do the capture and output, and people edit on the iMacs.
So…if you are using DV…you are in luck. Anything else…outta luck. Sorry
Shane

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