Improving DP & Actor Communication: Shot Designer, Phone Rehearsals?

Hey everyone,

I'm a Key Grip on a new indie feature, low/mid-budget, shooting on a V-RAPTOR XL with Cooke S4s, mostly interiors. We're trying to keep the schedule tight and communication efficient. I've heard DPs and directors talking about using things like Shot Designer, or even just filming blocking on a phone during prep, to clearly show actors and the crew what's going on.

My current pre-pro usually involves just walking through scenes with the DP and director, sometimes scribbling on floor plans. It works, but on bigger blocking days, there's often a bit of back-and-forth once the actors are on set, which eats up time we don't have. I'm wondering if a more visual approach could help us all get on the same page faster. I've toyed with Shot Designer on my iPad a bit, but haven't really integrated it into a project workflow.

For those of you who use tools like Shot Designer, or just simple phone rehearsals, how have you personally integrated these into your pre-production to genuinely improve communication with your DP and actors on set? What's worked for you, and what are the pitfalls?