FB4

[norty303]

Ok, so I had to send an email to Bill about something else, so I thought I'd enquire about FB4 and Apollo/Gemini whilst I was typing....

Here is the [slightly edited] response:

We put the Gemini project on the back burner for now.
We originally believed it was necessary to go that route -- having a "local computer" generating content for each scanner, in order to get the smoothness that we get with our QM2000 and also FB3 directly connected to a computer. In the past we never believed it was possible to get smooth output with a "network connected DAC" like other people do it, but then when one of our programmers spent a full year and developed a brand new network protocol running on FB4, we changed our minds and kind of back-burnered the idea of Gemini. FB4 will no doubt be much less expensive, much smaller, etc. while still delivering smoothness we see from QM2000 and FB3 directly connected to a computer.

I have some queries, but I haven't been back to him yet as he's pretty busy by all accounts, but the reference to 'new network protocol' says to me (I'm no network technician, it should be noted ) that it might use cat5, but not over a traditional network (akin to the USB extenders referenced above). What will be interesting to see if if it uses all pairs on the cat5, and if so, whether FB4 has provision for interlock control.

The dealbreaker for me on all of these things is whether or not I have to run an additional dedicated eStop cable or not.

[dave]

Klotz hybrid cable

Power, network, and a digital pair which could be used for interlock.

That being said, it's not cheap at ~10 euro per meter

[norty303]

Surely someone does 5 or 6 twisted pair cable for reasonable money? Or do people just double up on cat5? Can't think why I'd want to run power from stage to FoH either.

[dave]

I usually just run 2 cat6, one for gig ethernet, one as a spare which is used for interlock

[norty303]

This situation would upset my OCD terribly.
At the moment i run individual ILDA runs (eStop on interlock pins) and having to run 2 cables is not far off what I currently do. I need progress

[sbk]

That would be just boring to have to double the ethernet cable from stage to computer - when you already invested into high grade cables (rugged PUR, neutrik ethercon etc).

But I'm wondering about the "smoothness of output on a networked DAC". I actually use a Fiesta.NET since years and noticed no smoothness issues so far. I mean, you can do some pretty good things with a simple 100Mb network connection, it's all about correctly buffering datas and handling them at the received side...

[mystery123]

There's really not much knowledge or programming required to create smooth laser output in real time on Ethernet laser show controllers, even over Wi-Fi antennas (if the signal is stable of course). One 100Mbit line is about 6-8MByte without any problem. If you run your laser at 100000pps, the data flow is about 1MByte - so one 100Mbit line can easily handle up to 6-8 lasers running at 100000pps (which is not required of course). Not to mention, it's pretty standard to gave 1Gbit Ethernet output nowadays...

[dnar]

There's really not much knowledge or programming required to create smooth laser output in real time on Ethernet laser show controllers, even over Wi-Fi antennas (if the signal is stable of course). One 100Mbit line is about 6-8MByte without any problem. If you run your laser at 100000pps, the data flow is about 1MByte - so one 100Mbit line can easily handle up to 6-8 lasers running at 100000pps (which is not required of course). Not to mention, it's pretty standard to gave 1Gbit Ethernet output nowadays...

Bandwidth alone does not adequately define the full picture. Larency is a big considerarion, and while high latency can be worked around, this and other applicarions benefit from low latency transports.

[mystery123]

No latency if you connect cable. No latency if you use good WiFi. If we can play video over network- laser is nothing...

[sbk]

Latency is no problem with ethernet. What could eventually be problematic is "consistency" (real time operation). But ethernet is a pretty solid thing... If you wanna go rock solid, you could implement some LXI communication (class A or B)