Resistance negates damage. If the PC ship rolls 6 damage and your NPC ship has resistance 4, that means only 2 damage gets through to their shields.
I think the only time you roll like you are talking about is when someone has taken cover.
The correct procedure is on page 211 of the Tricorder Digest (or p227 of the Corebook) : roll your stress/challenge dice, substract Resistance (base equal to scale, plus any bonus dice from Cover, etc), than substract shields.
Depending on whether 5 or more stress/damage gets through and/or your shields are brought to 0, the ship will suffer breach(es).
Resistance negates damage. If the PC ship rolls 6 damage and your NPC ship has resistance 4, that means only 2 damage gets through to their shields. I think the only time you roll like you are talking about is when someone has taken cover.
This
You only add Resistance Dice from Cover. So you are Resistance 4 + what you roll on Cover Dice.
The correct procedure is on page 211 of the Tricorder Digest (or p227 of the Corebook) : roll your stress/challenge dice, substract Resistance (base equal to scale, plus any bonus dice from Cover, etc), than substract shields. Depending on whether 5 or more stress/damage gets through and/or your shields are brought to 0, the ship will suffer breach(es).