“Latency” – what’s that you ask? In this context, latency refers to the time it takes for the video signal to transit one part of the IMAG path, from camera lens to final display. Latency is usually expressed either in milliseconds or in video “frames” (typically either 25 or 29.97 to the second.)
As we said above, really a little video latency is not a bad thing as viewed from a surprisingly short distance back into the audience. This is just as well, since for all practical purposes a little latency is also unavoidable.
Even so, as long as audio and video are in sync at your seat, only a rather ‘significant’ degree of latency will be objectionable – unless you happen to be very near the stage. For those in the front rows, a few extra frames of latency may be rather disconcerting. (It’s true that IMAG was conceived primarily for the benefit of those further back, but if the latency is too obvious for those nearest the front it can be disconcerting distraction.)
For this reason, it’s desirable to keep video latency to an agreeable minimum – but put away any notion of ‘zero latency.’ Not only would this require bending the laws of physics, it would be a bad idea.
Even before considering minimizing latency in the device chain, acknowledging that there is always going to be some latency calls for some creative thinking with regard to practical staging. For example, if you design your IMAG layout in such a fashion that those in the front row are unlikely to be able to see the screen(s) without lifting their eyes from the onstage talent, they are extremely unlikely to notice a small amount of latency.
For more information please download the entire document at new.tk/rt-m