Camera 2 latency

I am new to BoinxTV and using it to do a news show at my elementary school. I am having issues with the second camera on my macbookpro. The issue is that the second camera is acting a bit “strobe-like”. I thought at first that the problem was that I was doing greenscreen with both cameras and having two different background layer. That wasn’t it, I also switched camera cables, this also didn’t fix the problem. Somewhere I read that I should change the framerate for the camera, but I don’t know if that is a setting in the camera or within BoinxTV, or if it even makes sense. Send me some ideas please

Hi Dave, are you bringing in the 2nd camera through a firewire express card or are you straining the single bus on the macbook pro? The reason I ask is that we saw a kind of “strobe-like” behavior when we attempted to use one more camera than we had busses on one of our macbookpros. With a firewire express card we were able to stream 3 cameras on a macbookpro, but the 3rd was not reliable enough to use professionally because of the intermittent strobing.

Altplanet, Thanks for responding! My macbookpro has 2 firewire ports, each hosting a camera. Even when I switched the port on the camera it was still giving me trouble. I swapped out the 2nd camera this morning with better results although now my video is lagging the voice. I have mic’s plugged into a mixer board and the output of the mixer into our modulator, then out to the school. I think if I can figure out a way to send the output of the mixer into the computer, then out to the modulator my video lag might get fixed. Do you know how to route the audio from the mixer into the macbookpro, then back out again? Thanks

Can you specify what you mean with “strobe like”?
About the Firewire bus issue:
Normally one Firewire bus can only hold one camera (at least from the same vendor). Cameras from the same vendor tend to have the same firewire ID baked into the system and it can’t be changed. Like this the two cameras collide on the same bus and only one can be used. So in most of the cases you will need a dedicated bus for each camera. This is also why e.g. Firewire hubs don’t work. On a MacBookPro you can add a firewire expresscard to get a second bus and on a MacPro this can be done with multiple PCI-Express cards to gain multiple additional busses. Both cards can be found at

Cant you just send your audio to BoinxTV and on from there?