Best practices for solid RF when shooting car to car

[BAB414]

Hey all,

 

I have a scene coming up involving a character singing to the radio in a small convertible car, shot with the Russian Arm/Ultimate Arm. I will drop the bag in the backseat and am planning to ask the non-driving character to hit play on a small phone feeding an earwig. In case playback NEEDS to be triggered by someone not in the car, what can I do to ensure the cleanest signal for the earwig?

 

I have not had good experiences with talent Tx in one car and my Rx in another car. I sometimes get decent range on the 216MHz comteks going to a follow van. However, I think it's important to have the earwig Tx in the picture car. So should I hop the signal over with an SMQV at 250mW in the chase car to a 411 that feeds the BST? I'm planning on worst case scenario where we see the entire car. Any other tips or tricks?

 

Thanks!

[Wyatt Tuzo]

Just, just did this.

I agree that you’re going to want the base station in the hero car. 
In my case, we ended up switching to a tow rig on the day. I rode on the back of that, took PB into my recorder, and transmitted via UH/411 to my base station in the car. I was prepared to do the same from a command van, but again… last minute change, as they wanted a frontal 2-shot. 
I’m rambling a bit here, but bear in mind that if the performer is singing along to a known song, you can also have a speaker playing at a reasonable level in the vehicle. They are going to have to cut around the song anyway, and this will just worldize the track a bit. 
For car to car, I generally try to get my Tx high in the hero vehicle, and rig my antennas to the top of the follow vehicle. With an ultimate arm, you may not have that luxury. Are you sure they dont plan to shoot conventional coverage as well?

[Olle Sjostrom]

15 hours ago, BAB414 said:

”…shot with the Russian Arm/Ultimate Arm. ”

I think it’s called U-Crane nowadays

 

anyway, I agree with Wyatt. You can play the track conservatively through the speakers of the car if you can wire it up properly, A transmitter from your bag wherever you are.

One solution I’m dreaming up is using a SIP or WebRTC transmitter through phones. I have a daily job in radio broadcasting nowadays and we use our own SIP server to connect devices all over the world , phones or dedicated hardware. I could really see a use in movies and cars. There are apps and solutions for it, the simplest one being Zoom (which is heavily encoded, yes, but still sounds good enough for playback to phones). 

[BAB414]

Thank you both for the suggestions. Worldizing with a speaker is a great idea and a backup plan in case the earwig doesn't cut it.

 

They plan to also cover the scene with a process trailer on a different day, where I will have more flexibility. The hardest part of all of this has been getting their attention, followed by getting answers to my questions.

 

I also thought about a phone system as a transmitter/receiver but we will be in the middle of nowhere so I can't know for sure if there will be any service out there.

[Wandering Ear]

The arm car is likely to stay fairly close to the picture car. Maybe you can trigger playback from there if necessary?  Many times i have been in follow vans where I’m promised we’llbe close and stay in range, just to find on the day we end up out of range of a Comtek bst75 mounted up high in the car, or just pulled over and parked as they free drive back and forth coming in and out of range. 
+1 to keeping the earwig tx in the car. Earwig reception is finicky enough as it is. 
 

this gives me another idea that i might build and test one of these days. I could easily build a website where you load the playback file and then have the site open on a phone in your car, and also open on your phone in the van and can control the playback from your van phone.  It would require at least some cell service, but would require much less data than streaming the audio since it would only need to send/receive transport controls and would not have audio dropouts when the service gets poor.   If this is something anyone is interested in, let me know and I’ll build a quick proof of concept. 

[BAB414]

17 hours ago, Wandering Ear said:

The arm car is likely to stay fairly close to the picture car. Maybe you can trigger playback from there if necessary?  Many times i have been in follow vans where I’m promised we’llbe close and stay in range, just to find on the day we end up out of range of a Comtek bst75 mounted up high in the car, or just pulled over and parked as they free drive back and forth coming in and out of range. 
+1 to keeping the earwig tx in the car. Earwig reception is finicky enough as it is. 
 

this gives me another idea that i might build and test one of these days. I could easily build a website where you load the playback file and then have the site open on a phone in your car, and also open on your phone in the van and can control the playback from your van phone.  It would require at least some cell service, but would require much less data than streaming the audio since it would only need to send/receive transport controls and would not have audio dropouts when the service gets poor.   If this is something anyone is interested in, let me know and I’ll build a quick proof of concept. 

This is a rad idea!

[Izen Ears]

Mag mounts for all the tx + helicals mounted to the roof of your car = great range!

[Wandering Ear]

8 hours ago, BAB414 said:

This is a rad idea!

Ok cool. I’ll try to throw together a proof of concept this weekend and see how it works. 

[Rick Reineke]

I have fed (mic level)  audio to a walkie/talkie with a custom adapter cable I made. It was not recording quality but plenty good for monitoring. RF range was that of the walkie/talkie system. a mile or so. I suppose it could be done in reverse. Tx in the follow car and Rx in the picture car.

[Mungo]

You could use FM transmission from the follow car to the car audio system which must be set to a very low volume.

If you mount the FM tx outside and high above ground that should work fairly, especially in a non urban area as mentioned. Also because car audios usually have a quite good reception stage.

 

I know about shows here where the other way round is done frequently: director crew in the follow vans listen to the recorded dialogue in the play car via their car audio.