GH1 and GF1 as broadcasing solutions

Vitaliy Kiselev

Vitaliy Kiselev

Carbonite Member
I have simple questions for people in this field.

Lets suppose that GF1 and GH1 will be able to output live HDMI.

Main task is to make small studio that have up to 7 cameras at fixed positions.

Cameras will be connected to HDMI switcher.

And this switcher to H.264 Pro Recorder - http://blackmagic-design.com/products/h264prorecorder/ .

Resulted stream will be broadcasted online.

As I understand main problem here is HDMI switcher, as we can have artefacts (black frames or similar things) during active camera switching.

Is it possible to find other cheap solution?
 
I would use a HDMI to HDSDI converter for each camera.

Feed the HDSDI signals into HD Frame syncronizers to match scan rates so you can switch between cameras without any glitches. We use the Evertz unit at our facility but there might be a more affordable version I am unaware of.

Feed them all into an HDSDI switcher.

Sync via a blackburst or tri-level sync generator like Evertz MSC5600 or Black Magic feeding frame syncronizers and video switcher.

I use all the gear I linked to above and can attest to it working for the purpose you mentioned.
 
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no idea what any of this technical mumbo jumbo means. but Vitaly, is this hint that you are getting close to unlocking HDMI Live Out on GH1? :)
 
fraustosound said:
I would use a HDMI to HDSDI converter for each camera.

Feed the HDSDI signals into HD Frame syncronizers to match scan rates so you can switch between cameras without any glitches. We use the Evertz unit at our facility but there might be a more affordable version I am unaware of.

Feed them all into an HDSDI switcher.

Sync via a blackburst or tri-level sync generator like Evertz MSC5600 or Black Magic feeding frame syncronizers and video switcher.

I use all the gear I linked to above and can attest to it working for the purpose you mentioned.
Click to expand...

Thanks, I know about this solution. HD-SDI is generally used for such tasks, yes.
Problem is that this is little overkill for this project.
I am ok to tolerate small sync problems during switches (audio will be separate anyway), but not black frames.
 
I don't know how to avoid black frames without frame-syncronizing all your sources. Let us know if you find a solution. Good Luck and thanks for all your hard work!
 
May be HDMI to component (so I can place it with very short cables near switcher) and component switcher will be suitable?
 
Hi Vitaliy: I was only able to find a few switcher/mixers with HDMI video inputs that can do what you want, e.g.: switch among multiple non-genlocked HDMI sources without visual glitches.

For example, Roland makes more than one HDMI mixer/switcher, but they only have a couple HDMI inputs (maybe convert some sources to HD component or HD-SDI ... should be less expensive than converting all sources to HD-SDI):
http://www.rolandsystemsgroup.com/en/products/edirol-by-roland/video-mixing-mainmenu-386/v-1600hd
http://www.rolandsystemsgroup.com/en/products/edirol-by-roland/video-mixing-mainmenu-386

This Panasonic unit doesn't have enough HDMI inputs for your application either:
http://catalog2.panasonic.com/webap...Id=452711&catGroupId=37051&surfModel=AG-MX100

I'd be curious to know if there are others.

- Peter
 
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It is to overkill of this project (plus not enough inputs).

If Blackmagic could make same recorder with, say, 8 inputs and software seamless switcher it could be very-very popular in some fields (like studios who broadcast online).
LCD and controls are not required as operator have laptop with picture anyway.
Other approach is to use Blackmagic PCI-E capture cards, but it also have amny problems (starting from H264 encoding and maximum really working cards). Plus no 60p support.
And it'll required real soon.
 
I've never heard of a studio running off HDMI. It just isin't done, you can't run it far enough for most purposes. You really want to convert to HD-SDI or component at the least. Since the GH1 can't genlock it might cause you a bit of a problem. In our studio we run cheap extra cameras through a TBC, the main cameras are all synced to a timecode generator and connected by Triax cable.
 
My experiments show that it can be done as I don't need more than 10m cable lengths.
Plus even 20m is not a problem as small HDMI amplifiers exists.
 
But that's not really the point, and extenders would just be an extra hassle. A converter+cable for HD-SDI or component will cost as much as HDMI cables, but it's a lot more flexible. You might not want to go over 10 meters NOW, but you might want to down the road. Plus, it opens up a lot more options for not only a switcher, but equipment in general.
 
Yes. Problems is I'll never need more than 10m in this project.
Plus 10m cables cost few dollars compared to abot $300-$400 for each converter.
As for SDI equipment it is just outside of possible price range.
 
I've used 25m long HDMI for bluray to projector connecetion and didn't have any problem. It was good cable with gold plated connectors but don't think that really matters. Didn't try with GH1 as that was happen way before this camera.
 
Wow, lots of tension in this thread... I think Vitaliy may be on a budget and he never said this was for tv broadcast, it could be an internet broadcast and not need all the bells and whistles and convertors etc.

Otherwise a lot of decent feed back, If you are trying to create a broadcast for local tv etc. Then going full HDMI is some what nonsense(not just signal reason, physical ones also) I would at least use an HD Fury and go down to component but then again that might be outside the price range.

It seems like no one will really have the answer he is looking for.. He made up his mind on what he wants and needs and is looking for it... Re suggesting something he does not want over and over again wont help him. Maybe if we can have some more detail on what the final outcome or end result is we can give him some better ideas that fit into the type of setup and budget.
 
I clearly stated that this will be online translation (plus later, possible limited cable distribution), no TV and all this related stuff. Budget is tight and I must have ability to scale this thing for cheap (make 2x-5x of same setups). SDI is clearly not a suitable solution.
I am ok to tolerate few frame freeze during switching, but not 2sec black frames.
 
@vitaliy , I got it, was just making a statement to others that this was not brought up as tv broadcast so no need for $800 adapters and all that jazz.

The least we can do is put in some elbow grease, I sent out an email to a friend at local news station they are doing some weekend segments on canon cameras in a new section of the studio. I know they have 5D mark IIs so I hope to have some insight for you. i know it's Broadcast but maybe we can get some ideas on how they are doing it.

Maybe we can even get some donations for all the nice work you have done for us and help bring up that budget :) this does mean HDMI out after all.
 
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