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Martin
14-05-2004, 11:31 AM
After fiddling all night i found something out regarding the BMD cards.

We are using a Decklink standard and a Decklink extreme each in its own G5. We running two SDI feeds from the trucks. The Decklink standards can take both signals without any problems, while the Extreme can only take one of the signals properly. After talking with Black Magic for an hour, one of their engineers realized that because the Decklink standard has its connectors on the card itself, it is much less sensitive to bad signals, while since the decklink Extreme has an monster cable between, it makes the Extreme more sensitive. In this case a booster helped, or actually a scanconverter that has SDI in and Out. Everything is running smooth now.

Morale is: Cheapest card works best. If you do not need the Gen.lock functions, buy the Decklink standard.

Martin
17-05-2004, 02:14 AM
Sent to me from Ross via email

Hello,
I could not get my Decklink card to work. Catalyst could not see the SDI input. Can you explain the method and or order you used to install the card and drivers?

Many thanks,

Ross

Hi Ross.

I Installed the drivers, and selected SDI input in the controlpanel, and Catalyst found it. We really did not have any trouble with this.
What we did have trouble with was the SDI signal. if your screen says "No video input" then i would check my signal first, or use a booster. This is pure speculation, but i suspect the decklink cards have been built to do editing in a studio where your decks are located 5 meters from your computers, and not 100m from a OB-truck.

What type of decklink did you get?

Martin

samsc
19-05-2004, 12:10 AM
No video input. definetly means your sdi input signal is missing.

You only get this message if the driver and software is working.
This doesnt come from my software it comes straight from the driver.

samsc
19-05-2004, 12:12 AM
We are using a Decklink standard and a Decklink extreme each in its own G5. We running two SDI feeds from the trucks..

Im not sure you can use two standard cards in the same machine.

Can you?

You couldnt last time i emailed them.

Sometimes people want a composite signal as well i guess.

rosswill
19-05-2004, 01:44 AM
No video input. definetly means your sdi input signal is missing.

You only get this message if the driver and software is working.
This doesnt come from my software it comes straight from the driver.

Not true. Tested sdi source with pro broadcast sdi tester. Sadly didn?t have time to check again today with the new drivers off the web. Will report back soon.

samsc
19-05-2004, 06:41 AM
Not true. Tested sdi source with pro broadcast sdi tester. Sadly didn?t have time to check again today with the new drivers off the web. Will report back soon.

or your sdi is unreadable....for whatever reason.

The no video input signal comes from decklinks software - not mine - if you get this it means decklink drivers are initiailsed installed and working.

Did you install the drivers on the disc? what version?

The number one thing you need to do is run the BMD application : "Blackmagic Deck control', their installer software puts this in the application folder.

This just eliminates any catalyst issues.
They also have a control panel that installs in system preferences.

You should turn off the 'Video desktop'. this doesnt change anything. its just confusing for this stuff.

You can see the blue 'no video input' message in the image below coming from BMD Deck control app.
The system preferences are from the Decklink extreme,

samsc
19-05-2004, 06:57 AM
People need to remember that setting up no hardware or software system is ever foolproof or easy enough.

People need to test things and become comfortable with new things away from gigs, preferable not in front of the client, where the vagaries of this stuff are gone through.

It doesnt even have to be complex hardware that can cause a lot of problems.

Cabling problems, wrong connectors, wrong pinouts, wrong cable assumptions, cause as many problems as pci cards.
This has been the case throughout my entire time in this industry.

On Jerry Springer the musical. we were trying for days and days to communicate with an NEC projector to open and close the shutter.

I tried everything. In the end i discovered that the installation had not been carried out correctly, and the cable to the projector just didnt work and had never worked.

I assumed the installer 'would have tested this...' stupid me. They just ran a 100ft 'rs232' ( mike ) cable to the projector with no buffering without testing whether it was going to work.

I did all the right things, including plugging directly into the projector, but this was fraught with difficulty as the projector was not easy to get to and required technicians.
And the projector settings were nearly always unreadable as there was no easy screen.
Projector documentation was as confusing and old as it always is - normally from a model that was discontinued 3 years ago.

Martin
19-05-2004, 07:22 PM
Im not sure you can use two standard cards in the same machine.

Can you?

You couldnt last time i emailed them.

Sometimes people want a composite signal as well i guess.

You cannot have the two same Decklink cards in the same machine. The reason we had one standard and one extreme was because of availability issues. We have fitted our G5´s now with one Miglia card and on Decklink.
Gives you SDI, component, composit and S-Video input.

Martin
19-05-2004, 07:25 PM
or your sdi is unreadable....for whatever reason.

The no video input signal comes from decklinks software - not mine - if you get this it means decklink drivers are initiailsed installed and working.


Exactly! We did get a SDI signal, only not "good" enough for a Decklink extreme. We checked the signal on a SDI monitor, and we got a perfect picture. When trying in the Decklink Extreme, we got no input. The Decklink extreme apparently are more sensitive for weaker signals. We got a booster in the end wich cured all our worries. The Decklink standard however worked all the time.

samsc
19-05-2004, 08:15 PM
Exactly! We did get a SDI signal, only not "good" enough for a Decklink extreme. We checked the signal on a SDI monitor, and we got a perfect picture. When trying in the Decklink Extreme, we got no input. The Decklink extreme apparently are more sensitive for weaker signals. We got a booster in the end wich cured all our worries. The Decklink standard however worked all the time.

then maybe there might be impedance mismatches with that enormous cable...

samsc
19-05-2004, 10:26 PM
thanks martin for being so persistent in trying to get to the bottom of your problem.

looks like this will help ross too.

im not an expert on sdi distribution.
so i cant help from experience.
but sdi will be prone to impedance mismatchs just like any high frequency signal.
its clock rate is around 250Mbit/s i think....so its pretty fast.

samsc
20-05-2004, 07:12 AM
then maybe there might be impedance mismatches with that enormous cable...

Or maybe the extreme card cable is designed to be plugged directly into a deck. so that its termination works?

Maybe - It doesnt work if you join it to another sdi cable coming from another piece of gear?

Martin
20-05-2004, 01:54 PM
Or maybe the extreme card cable is designed to be plugged directly into a deck. so that its termination works?

Maybe - It doesnt work if you join it to another sdi cable coming from another piece of gear?

Black Magic told me that the Extreme is more sensitive to SDI than the Decklink standard, because the Extreme has the monster cable, while the Standard have the SDI connectors soldered directly onto the card.

Martin

samsc
20-05-2004, 05:29 PM
Black Magic told me that the Extreme is more sensitive to SDI than the Decklink standard, because the Extreme has the monster cable, while the Standard have the SDI connectors soldered directly onto the card.

Martin

they mean more 'sensitive' to wrongly/badly terminated sdi cables.
means they got something wrong on their board.

rosswill
20-05-2004, 06:16 PM
I'm talking to Blackmagic about this. Hopefully we will get to the bottom of it all.

samsc
20-05-2004, 06:25 PM
I'm talking to Blackmagic about this. Hopefully we will get to the bottom of it all.

you wont get anything fixed soon talking to them.

Did you try using a sdi amp/distribution panel?

samsc
21-05-2004, 06:38 AM
And SDI chip application note from xilinx:

http://direct.xilinx.com/bvdocs/appnotes/xapp247.pdf

samsc
27-05-2004, 11:51 PM
Ross.

Did you sort this out?

R