Yes, you want an incident meter. I'm partial to the Sekonic 558 for studio and for street I've always used a Gossen, first Luna Six then a series of Digisixs.
The advice given thus far is great. There is one more issue: Your Exposure Index for specific films. Box speed for film is usually a suggestion, a starting point. Through experience I find that TriX 400 in 35mm is ISO 250, in 120 ISO 200, and the 320TXP in 4x5 and 120 is really ISO 320. Then there is TMAX which, in rolls, is really close to box speed when souped in TMax developer. Sheets in HC110 should be shot (in my opinion) 1/3 over. Color film is another ball game. I find 35mm Kodak 400UC to be really great at 200. You get the point. My suggestion would be to shoot it on film, but also shoot some digital so you have a predictable result for the happy couple.