Hi… this is quite newbie but it’s something I’ve been wondering. During combat, while you still have shields remaining, does it make any difference to apply any active armor hardeners? Like… does it only make sense to activate armor hardeners once all shields have been depleted and you are actually taking armor damage? It seems like that’s how it would be but … I just want to make sure
Usually you turn on your hardeners on the begin of the fight, because on any ship that is armor-tanked in a way that you use active armor hardeners, you can simply ignore your shield (rare exceptions not relevant for a new player).
However, in general I would recommend for a new player to use either an Energized Membrane (C-types can be cheap) or an A-Type Coating (the single-resist ones are usually pretty cheap) for passive resistance enhancement. Simple reasons: They don’t go offline once you run out of cap, and new players should start with managing as few modules as possible at a time and propmod+weapons, the basic flight maneuvers and constantly reevaluating the combat situation already stress them enough. Begin using active armor hardeners if you really make use of emergency overheating, which is their greatest benefit over passive modules.
In a capstable PvE fit you can of course use Hardeners to tank a specific NPC damage type, but then turn them on right from the beginning and ignore them.
In a lot of small scale PvP situations the question of hardeners is about when to turn them on preheated. Low slots don’t typically generate heat and hardeners have longish cycle times so in a lot of situations people only turn them on and already overheated. The increased resistances helps both buffer and active tanks so its commonly desirable in lieu of overheating armor reppers directly. Usual overheat considerations apply.
The smaller considerations:
Unless you have TSM V you will bleed damage from shield into armor when your shields are below 25%. Whether to get TSM V is one of the longest running debates about whether it’s a skill that harms you as you level it up.
Reactive armor hardeners need time to adjust their values to be effective. The more uninterrupted cycles it has, the closer its resistance profile will match incoming damage. Matching this profile is important, otherwise it is subpar. If you were taking armor damage but received shield reps, turning off the reactive armor hardener would lose its already matched matched resistance profile and next time you entered armor you’d have to restart the matching process, harming your survivability.