FB3 and RJ45 (cat5)

[andy_con]

ok thanks for your comments guys

[Stoney3K]

That's a sweet idea.. wish i had room in my cases for that stuff. I currently use VNC software to solve my cabling issues, but there is a tiny bit of lag introduced when remotely controlling another computer.

IMO, there is no need for millisecond-accurate sync when you're running shows live. And when you're not (e.g. prerecorded or directed), you can wire your system to run off time code for most situations.

I once ran a show where I parked my laptop backstage with two FB3's connected to it, and I had a tablet PC which was connected to the laptop via VNC. That way I could just sit in the main room and watch the show from the audience POV, just tapping the appropriate cues in Quickshow. Worked amazingly well.

Would it be an idea to research a 'digital' version of ILDA which can run over standard 8P8C network cable, 110-ohm XLR cables, or maybe even optical fiber? Multi-channel ADC's and DAC's are easy to get right off the shelf, and there is not a lot of additional infrastructure you'll need, except for multiplexing. An 8P8C (8 conductor, RJ45) CAT5e network cable could run the frame signals, along with interlock and shutter hard-wired, and even have a wire pair left over for return or other additional bells and whistles.

[Things]

I have used those direct USB to RJ45 converters on the FB3. It works. Keep in mind though, longer runs = higher ping reply time. If a USB device doesn't reply to it's ping fast enough, it becomes a bit dodgy. That and long runs pick up interference, which USB does not like at all.

A more sensible thing to do would be to use the wireless method, or simply extend the DB25 cable thru cat5. Although, this might require a buffer over long runs.

[Lexat8]

Evening All!
I'm running one of these at 50m with an FB3, with a breakout board to two additional heads, running five scanners in total. Piss cheap too

http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT

Cheers

Lex

[andy_con]

Evening All!
I'm running one of these at 50m with an FB3, with a breakout board to two additional heads, running five scanners in total. Piss cheap too

http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT

Cheers

Lex

thanks for that, how do you have the projector end wired as you have 25 wires??

[ElektroFreak]

Looks to me like the purpose of those adapters is to extend the USB cable run between the computer and the FB3 instead of the ILDA connection between the FB3 and the projector.. You could then keep the FB3 near the projector, connected with a very short ILDA cable, and run the USB connection between the FB3 and the control computer using CAT5.. at least that's how it looks to me.

[andy_con]

good point .

[ElektroFreak]

Would it be an idea to research a 'digital' version of ILDA which can run over standard 8P8C network cable, 110-ohm XLR cables, or maybe even optical fiber? Multi-channel ADC's and DAC's are easy to get right off the shelf, and there is not a lot of additional infrastructure you'll need, except for multiplexing. An 8P8C (8 conductor, RJ45) CAT5e network cable could run the frame signals, along with interlock and shutter hard-wired, and even have a wire pair left over for return or other additional bells and whistles.

That sounds like an awesome idea, but I'm not 100% sure if it would be worth the work when there are several ways of dealing with difficult cable runs. Digitizing ILDA would have benefits like compatibility with existing network infrastructures and noise immunity, but there are other, perhaps simpler, ways of accomplishing both. IMO of course..

[Lexat8]

Looks to me like the purpose of those adapters is to extend the USB cable run between the computer and the FB3 instead of the ILDA connection between the FB3 and the projector.. You could then keep the FB3 near the projector, connected with a very short ILDA cable, and run the USB connection between the FB3 and the control computer using CAT5.. at least that's how it looks to me.

Thats how I do it. The to satalite heads connect via ILDA breakouts from the main head.

Lex

[Stoney3K]

That sounds like an awesome idea, but I'm not 100% sure if it would be worth the work when there are several ways of dealing with difficult cable runs. Digitizing ILDA would have benefits like compatibility with existing network infrastructures and noise immunity, but there are other, perhaps simpler, ways of accomplishing both. IMO of course..

As far as I see it, I try to avoid "network" infrastructures (e.g. multi-node bus systems or switched point-to-point systems with multiple transmitters) for mission-critical stuff as much as possible. Multi-drop is no problem, but multi-node has the big drawback of possible collisions and switching latency.

That's also the reason why I don't use digital multi-cables for sound mixers. On paper they work fine, but when push comes to shove there WILL be a gig when you have an audio drop-out. DMX512 is fine, because it's multi-drop and not multi-node (if you don't count RDM).

Furthermore, ILDA itself is a downstream-only protcol (in fact, based on the same 0-10V voltages that were once common on dimmers in the before-DMX512 days) and it's therefore easy to digitize in a single direction first without having to rethink your entire setup. The advantage you get is that you gain a lot in physical infrastructure: A 110-ohm twisted pair cable is easier to transport and install than a 25-conductor shielded beast. Besides, if you're short on twisted pair cable, you can always snag a foot or two from the lighting guys.

ILDA also has the advantage of not requiring tremendous amounts of bandwidth. 6 channels of <20kHz analog signal is a piece of cake -- you could even encode it in lossless Dolby TrueHD and throw it on an AES/EBU wire.

EDIT: With regards to "compatibility", different projector manufacturers have different ideas on how to handle the remote interlock and shutter on-off signals, let alone different connectors. These are also worth a look, since I think being able to plug in every projector *safely* at the same time is worth the effort, at least.