Would it be best to use the same guy or should I find a different ADR guy who has a recording studio, etc?
Mussoman's suggestion would not result in seamless audio and would not be how professionals would handle ADR, Soundslikejoe's suggestion would be.
The advantage of a professional ADR studio is that you would get a neutral ambience, which is relatively easy to match during mixing. However, unless you've got a decent budget, you won't be able to afford a professional ADR studio and most recording studios would not do, as they're designed for music recording and rarely have a neutral ambience. The task during mixing is therefore that much harder because not only do you have to match the dialogue itself but you have to overcome the sound/ambience of the studio and match that too. In other words, at the no/lo budget level, Mussoman's suggestion might end up being the least difficult to integrate and the most appropriate.
Your production sound guy could be a good choice as presumably he'll have the same equipment as on the shoot, which should get you a closer sound match. On the other hand, does he have the additional equipment and experience required to record usable ADR? ... Probably not.
Also, should directors usually go to an ADR session with the actor and the recordist? Or should I just get them in conctact with each other?
There are two main issues with ADR: 1. Getting clean ADR which is easy for the Re-recording Mixer to handle and which is at least close to the timing of the original (so it's easy for the ADR Editor to handle) and 2. Getting a good performance; the appropriate enunciation, emphasis and emotional feel/realism in the ADR.
Even at the highest budget levels, achieving #2 is usually problematic. Who else would "direct" the actor to get the desired performance if the Director is not present?
G
