The wiki is probably really out of date, I need to get to that on my next pass, through the wiki. The rules for force fields, as they currently are, are pretty simple:
1. When a ship fires OUT from under a force field that is protecting it, it's power is reduced to 1/4 of normal. Or, put another way, it's 75% less effective. There is no ability or method for eliminating this reduction for your ships, aside from not putting them under force fields.
2. When ships shoot IN at a ship under a force field, normally the force field just absorbs the shot and is damaged the exact same amount that the ship under it would have been damaged.
3. When a ship has the force fields immunity (it just says "force fields" under the immunities list), they can move through enemy force fields and shoot at ships that are under them as if the force fields aren't even there. There is no power reduction on these shots whatsoever from the ENEMY force fields, those force fields are a non-presence here. However, this immunity has no effect on the damage reduction from your/allied force fields (item #1 here).
4. The "fires through shields" ability refers to shields, not force fields, which is something completely unrelated.
So, in summary, based on #1 you want your turrets and so forth outside your force field, otherwise you're really making them pretty ineffective. Meanwhile, anything that you want to protect goes under the force field so that it stays alive. And if you're attacking an enemy force field with ships that are immune, you don't have to worry about your ships losing attack power from that in any circumstances.
Hope that helps!