How Do Elemental Defenses Work?!?!

Do elemental defenses work as in: If I did 500 fire only smoke bomb, and I use it against a mob with 200 fire defenses, then would I do ((damage)-(defenses)*number of hits in the spell) which is (500-200)*10=3000 damage or does it work like: I don't know how to explain this but (500-(200*0.50))*10?

I'm sorry if this is kind of confusing, and if this IS, then just look at the title, and explain please... I don't understand... :P

Edit:Changed title to be more explanatory

 

pretty sure... but if the mob has higher elemental def than your elemental dam to the mob, it won't deal 'negative damage' (a.k.a. healing the enemy) just will deal 0 damage from that element I think...

I'm not an expert keep in mind

 

I think elemental defence is like:
E. Damage - E. Def = final damage

If final damage is negative, it becomes zero

 

Elemental defense is applied after ID boosts (sp elemental damage boosts, Str/Dex damage boosts, spell/melee/element percent boosts, etc.) but before the attack speed multiplier and spell multiplier.

 

so the spell multiplier (20% in the case of arrow storm, and dif for other spells) is applied after the elemental defense calculation? Meaning elemental defense is calculated when damage is 100% and then is multiplied by 0.20?

 

Yes. Motoki's damage calculation thread details all of this.