A common problem for us is trying to mic a subject who walks into the background and continues talking. This seems to come up a lot. In other words, we might have a group at a table talking, which is being miced with a cardiod on a boom pole. One person gets up and walks into the background and continues talking while the camera holds on the group at the table. Our director just really likes deep focus shots like this. My initial thought would be to put a second cardiod or an omni in the background and attempt to mix the two signals in post to sound continuos, but I've a read a few posts about boundary mics being used for stage productions and now I'm wondering if that wouldn't be the way to go for the second mic. We don't have wireless, and I'd rather avoid that route to tell you the truth. Hiding the transmitter would seem like a pain, not to mention taking time to tape up the lav, and I'm reluctant to invest in technology anyway that will just be illegal to use some years down the road because of impending changes to regulations on the use of available bandwidth. Any thoughts?

Since you're totally against wireless, then I won't mention that it would be an excellent way to achieve consistent sound quality with someone who is walking around the set. Obviously it does have drawbacks, but every solution you'll get here will have some negative aspects.
The success of a boundary mic is highly dependent on having a good boundary in the right place and pointing the right way. Then you have to relate this to the pattern of the mic and figure out a compromise that covers the area of walking without being too open to all sounds or too distant from the subject.
If the person is walking more than 6 or 7 feet, then it will be difficult for ANY stationary mic to get consistent results.
I would vote for using a more directional mic like a hypercardioid or a good shotgun on an actively moving boom.
If you have to go with a static mic, then I'd say use a hanging choir mic. These can also be used as a plant mic or even a pseudo boundary mic due to their small capsule size.

Marco - I have 2 AT 853 choir mics and I'm in the Albany area. Shoot me a response if you are interested.

m-c-a-v-a-n-a-3 @n-y-c-a-p-.-r-r.com

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