Also, if it was me and the light was up to it, I'd consider using XP2 [if you don't mind chromogenic films] as I find it gives a particularly nice looking with smooth/pale skin and it handles a one-stop push in medium format quite well. That also gives a little leeway with changing light or tricky to meter light. I wouldn't bother with a filter. I'd also be wary of using an older folder unless it had a good rangefinder on it, as I'm not sure who much leeway you'll have to scale-focus in lower light.