Gcam can improve to use on Arma 3, but the camera follow the object still have the Lag(or keeping lay back) problem, Its fine with the Arma2 in Patch 1.59, until Patch 1.60 release the prob just came out
program designer:
https://sites.google.com/site/giganarma/gcam
ARMA 3
1.59
:D
1.60.....
:(