Splitting the HDMI for the F3 - options?

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On the off chance and horrible choice by Sony IF the decided to only have the HDMI work by itself...

What are some production quality HDMI splitting options out there, and what are the risks/quality loss (if any) of splitting the signal to go to a recorder and monitor at the same time?

I know some options out there like the nano have a thru option, but thats not what I'm inquiring about. I'm looking for splitters, and any info regarding degradation of signal if any.

info?
 
Well hdmi is digital, there will be no signal degradation of any kind. It's either bit for bit accurate or the signal will not lock and nothing will be displayed. This is the advantage of 1's and 0's over analogs wavering voltage.

Any reason why you want to record the hdmi? it will be 8 bit, and isn't exactly the most reliable data transmission medium for anything super important. Go SDI whenever possible, and your recording device (unless it's the nano) will record the full 10 bit signal. Like you mentioned, things like the aja ki pro mini (great 10 bit recorder), has outputs as well. I know at least on the aja, all outputs are active, regardless of which input your using. If you are inputting 10 bit sdi, you can use the hdmi out of the aja to monitor.

If you're set on going the hdmi route, any splitter will do. Just make sure it's a powered one, and not passive. Those do not handle handshake negotiation between source and medium and that is definitely not suitable for a recording environment. They also have trouble handling embedded audio. Just grab a powered one such as this: http://www.newegg.com/Product/Produ...65&cm_re=hdmi_splitter-_-17-707-065-_-Product

And before someone tries to tell me the f3's hdmi output will support 10 bit: it won't. Trust me. deep color and extended bit depth support via hdmi is something no camcorder manufacturer has any interest in, assuming they even know of the possibility. I learned this the hard way with the ex1r. go SDI, it's a great, industry standardized connection and way of transferring image data (edit: I've found mention of 10 bit being a possibility for the f3's hdmi output actually, but like I said, don't count on it. I've also found mention that the f3 uses the same chipset for it's current output arrangement (before 4:4:4 upgrade), and that would make the hdmi 8 bit. So who knows)
 
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Fohdeesha said:
Any reason why you want to record the hdmi? it will be 8 bit
Click to expand...

I already was told by Sony that most likely it WILL be 10bit out of the HDMI, I am looking into the Ninja recorder and thus why I was asking the question. But thanks for the info, I guess any old HDMI splitter will do then, and I don't have to worry about issues.
 
Also just to touch on the topic of you saying "no one will want to cover 10bit HDMI" Well the Ninja was created just for that, it only supports 10bit HDMI and the wouldn't have invented it unless they had cameras that have the option for 10bit.
 
I was speaking of camcorder manufacturers. The ninja is great, but as of now there is not a single prosumer camera outputting 10 bit over hdmi, the f3 would be the first. I'm sure there's some boutique industrial cams for manufacturing process, microscoping, highspeed etc that may have 10 bit hdmi support, but I speak of filmmaking cameras sub 20 grand. The atmos went for 10 bit just to futureproof. Atleast I hope the future brings 10 bit output to commonplace
 
In my view by the time the Ninja comes out and is field tested by ops it will be NAB time with a few more entrants in the marketplace including the AJA Ki Pro Mini, that like the Ninja really doesn't exist yet. A couple of things that would concern me about the Ninja as a film producer, first would an insurance company cover the production if all your digital assets are being recorded to a device using an HDMI connector. I suspect the answer would be a resounding NOOOO. Second, having used an external recorder and know the myriad of settings you need to have on tap to make them useful, I am bemused by the fact, the Ninja people have not shown any detail about what is behind their options menu.

In my view, it's not even on the table until the menu system is revealed in its full splendor and second until it is in the marketplace and put through its paces by operators. This is a startup company and cannot rest on it's reputation the way that AJA can given the protrracted delay of the unit.
 
Well, it defeats the Ninja recorder option, but doesn't the Nanoflash output both HDMI and HDSDI regardless of which one you used for an input?

That would mean you could feed the recorder first, then look to an onboard HDMI monitor or EVF, while also sending an HD-SDI signal to video village.
 
Yes, but the Nano is 8bit instead of 10 bit. Still, I'll use the nano because its available now and I have one. I'll wait until the dust settles on the other recorders.

On the original question, I've used HDMI splitters and the prior response you received was right. They either work or they don't, with one exception.

An unpowered split causes a loss of power that results in only being able to use shorter cables. Still its pretty respectable. If your camera could power a 20' cable, using a 10' one isn't generally a problem. Split a third time and its a problem.
 
Fair point about the Nano being 8 bit. I was reading a different thread earlier where the advantages, cost points and errata of the offboard recording options were dicussed at length.

Personally, I own a Marshall 7" with HD-SDI loop through and a 24" Grade 2 LCD monitor for video village, also with HD-SDI loop through. I do have a cheapie Marshall 7" with HDMI in, but no loop out. So for me, assuming the F3 doesn't provide HD-SDI and HDMI at the same time as currently anticipated, the Ninja just isn't a good choice. I'd end up spending too much in adapters and converters to make it practical.

I'm going to wait and see on the external recorders. In a pinch when a desktop can be on location I have a Decklink HD Extreme card, which takes HD-SDI (or HDMI) in and can be captured directly to Prores422HQ. Just a pain in the butt to get it on a set.
 
One thing I do on occasion (on the EX1) is run the monitor on component and the Nano on HD-SDI simultaneously. There is no splitting that way unless the splitting is internal. That's another way to have simultaneous output.

Component is analog HD but its sufficient for focusing and doesn't degrade in the first cable if its a short run. I imagine (but don't know for sure) it will be the same on the F3.
 
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Join DateJul 2008LocationIndianapolis, IndianaPosts667
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Well hdmi is digital, there will be no signal degradation of any kind. It's either bit for bit accurate or the signal will not lock and nothing will be displayed. This is the advantage of 1's and 0's over analogs wavering voltage.

While you are correct that there is no signal degradation, the HDMI and SDI signals are nothing more than analog voltage levels. Over a certain voltage it's a 1, under a certain voltage it's a zero. A lot of people don't realize this.

The HDMI spec says the following:-

Single-ended high level output voltage, VH AVcc ±10mVolts
Single-ended low level output voltage, VL (AVcc – 600mVolts) ≤ VL ≤ (AVcc – 400mVolts)
Single-ended output swing voltage, Vswing 400mVolts ≤ Vswing ≤ 600mVolts
Single-ended standby (off) output voltage, VOFF AVcc ±10mVolts

Since the swing is differential on
the pair, the net signal on the pair has a swing twice that of the single-ended signal, or 2��Vswing.
The differential signal, swings between positive Vswing and negative Vswing.

This translates as a total swing of between 800mV and 1.2V


​
 
Just to update this... Not all splitters are created the same, AND no it is not just a digital signal and it "either works or it doesn't"... Thats totally untrue as for we had a splitter in Africa that had issues and would put out the HDMI signal with a weird green hue and some crunchy effect, and when we'd switch it to direct it would be normal. So thats not the case. It did in fact send a signal but not the full quality signal. So splitting is not the best ideas unless you are directly monitoring whats going to your external recorder from the output of that device. If we had been splitting and recording to a NanoFlash, we would have been screwed using a splitter.

So keep that in mind.
 
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