not stretching arms completely

[itsaburgerrun]

when i do push exercises i don't push it all the way up i push it halfway then let it fall back(controlled).
i do this mostly with chest/shoulder exercises i feel it better that way and it's more explosive(more fun also but anyway)
my question wasdo it still work triceps or just a small part of it ? am i isolating anything out ?

[boathead]

you are isolating your triceps out of the picture almost completely...it is at the halfway point through lockout that they are mostly recruited.