HPX in multi camera live production

J

Jasons56

Member
I'm working for a company that mainly does live production for corporate and entertainment events. I need 2/3" mounts in order to have access to long glass, and the ability to shade multiple cameras. We typically work with Sony DXC (D30/D50) setups in the standard def realm. That pretty much defines our budgets too. It appears that the HPX 500 along with the Camplex system and the optional paintbox may provide what we need at a price point comparable to our Sony standard def systems. Does anyone have experience with the HPX in this role?

Now - for the really dreaming part. I understand the HPX can shoot in 60 frames overcranked. If there was a way to easily index and play back in slow motion from the remote panel as a poor mans slomo system - that would really help seal the deal for us. Typically we are fine with fixed 1/2 speed for most of our slomo needs.
Am I dreaming or would this be a possible work flow?
 
I am in the same boat here:violin:

Camplex is a little to expensive for me, I was thinking of tapeing together SDI, Intercom, Power, and Remote control cables together, or TVPro Gear has their own system, similar to camplex.

I am thinking about putting firestores on each camera for ISO. Any cons?
I was looking at that HDSDI switcher from panasonic.
How are you going to get tally? I don't know of any way to do that with HPX500.
 
does the HPX500's RCU provide for tally input?

If not, it's not that hard to make your own external tally lights. I do it all the time.

- Mikko
 
Well, it's pretty simple electronics.

Most (decent) [and all professional] video mixers/production switchers will have tally signal outputs.

Normally these outputs are "open collector" meaning that they are get connected to ground when they get tally. So at the very simplest, you just take a lamp (or LED) and connect one side to the + of a power source, then the other side to the appropriate tally contact on the mixer. Then you connect the ground of the mixer to the ground (-) of the power source. When that source is selected, the tally pin connects the lamp to ground completing the circuit.

However most of these systems only switch a very limited amount of current. About enough for one LED or so - no much. Normally a transistor is used to amplify the tally signal to drive a brighter lamp/s, or a relay to amplify even more.

Done correctly the circuit will have "opto-isolators" between the video mixer's contacts, and the rest of the circuit. These act as electronic isolation to prevent shorts between gear from causing damage.


Some video mixers simply output power on their tally connections when they go high .. even easier to connect there.


For the actual lamps, I like to use 20mm red LEDs for most applications:
20mmLED.jpg

- They can be mounted in a number of places in a number of ways, and are night and big and visible.



Normally my tally circuits consist of a interface box, that connects to the video mixer's tally output through opto-isolators, and then drives open collector tally outputs through large transistors for decent current capacity in a solid state system. I then connect the outputs of the tally interface box in a standard way, using a nice semi-powerful 12v power supply. The outputs are always on XLR-3 connectors with the following pin-out:
1 = Ground (fixed, always connected)
2 = +12v (fixed, always connected)
3 = Tally ("ground", goes low when switched)

Then any 12v lamp can be wired in between pins 2 & 3. If I'm using LEDs, I put the appropriate resistor in the XLR connector for the actual lamp. Or you can use the ground reference on pin 1 and the signal on 3 to connect into other tally systems (like Camplex, or a RCU or CCU).

Using XLR cables allows for the simple extension of tally with regular locking mic cables.

- Mikko
 
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