Lidgar
Gongfarmer
I generally do not use passive perception.
If they are not actively searching the location of the secret door (i.e., they just walk by it), I have everyone's perception modifier, so I secretly roll for them as they pass by it. I use a negative modifier from -5 to -9 depending on what the circumstances are (i.e., are they moving fast, light conditions, etc.).
That is just to notice something about the wall when they are not actively searching there. They still need to use an active Perception check to actually find the door and an Investigation check to open it.
If they are not actively searching the location of the secret door (i.e., they just walk by it), I have everyone's perception modifier, so I secretly roll for them as they pass by it. I use a negative modifier from -5 to -9 depending on what the circumstances are (i.e., are they moving fast, light conditions, etc.).
That is just to notice something about the wall when they are not actively searching there. They still need to use an active Perception check to actually find the door and an Investigation check to open it.