Okay, I think I can explain the answer to your question pretty simply:
Since time is relative to considerations of space as applied to a particular system which is fixed relative to the other system to which it can be compared, the perception is relative to the observer and his location both in terms of time AND space (leaving out gravitational effects), considering his absolute frame of reference relative to a moving frame of reference that can be considered absolute only relative to the other frame of reference when moving in an absolute time-space continuum that is relative to the originally considered time-space continuum. Of course this is true only if you consider both frames of reference as independent only in a relative sense, or absolute if you consider both frames of reference to be linked in a universal manner, with totally independent matrices on both relevant axes.
Now assuming you have understood me so far the conclusion can be easily reached that therefore the two perspectives will be separated by a differential consideration of perspective equal to the sum of the speed of each system as measured from the other one, minus C as measured from a third unrelated system.
:-;
this was a joke of course