Black Level´s for Broadcast TV use

Barry Green · November 22nd, 2004, 01:37 PM

<<<-- Originally posted by Graeme Nattress : Greg, Setup is never added to a firewire signal as that is digital and digital never has setup.
Graeme -->>>

Correction: setup SHOULD never be added to a firewire signal. But unfortunately, on prosumer cameras like the PD150 and DVX, it IS.

The proper way for a setup menu item to work would be to only affect the analog output. But if you go into a PD150 and choose setup at 7.5%, it will also change the digital data that goes out the firewire port. Same thing with a DVX. That's a disaster waiting to happen, and should be avoided at all costs.

Pro broadcast cameras do it properly: the 7.5 only affects the analog outputs, never the digital recording/output. But on all the prosumer cameras I'm aware of, it affects both the analog and the digital, and that's a problem.

Graeme Nattress · November 22nd, 2004, 01:46 PM

Well, technically speaking you can't add setup to a digital signal because setup is a purely analogue phenonema. As I described earlier you can alter to video recorded so that it looks like setup has been applied, but this produces an "incompatible" DV tape. Also, the setup in this case is applied on recording rather than output, which is what the original poster was implying.

The best advice remains. Don't try and add setup in anything digital. And if you need to dub to an analogue tape, then either get a pro deck or a pro dub house to do it for you. Although I've had pro dub houses muck it up, so you've got to watch them carefully!!

Graeme

David Lach · November 22nd, 2004, 04:30 PM

So, anybody knows if the XL2 adds the setup to its analogue outputs or not? If it doesn't, my understanding is that blacks will always look crushed when monitoring live (even though the recorded signal will be fine).

Graeme Nattress · November 22nd, 2004, 06:19 PM

For monitoring live you just have to calibrate your monitor to the camera, and all is fine, and you should do this wether setup is added on the analogue outs or not. Essentially setup is a brightness control, so altering the brightness on a monitor is exactly the same electrically as putting in a proc amp and adjusting black level.

Graeme

November 22nd, 2004, 01:46 PM	#17
Graeme Nattress RED Problem Solver Join Date: Sep 2003 Location: Ottawa, Canada Posts: 1,365	Well, technically speaking you can't add setup to a digital signal because setup is a purely analogue phenonema. As I described earlier you can alter to video recorded so that it looks like setup has been applied, but this produces an "incompatible" DV tape. Also, the setup in this case is applied on recording rather than output, which is what the original poster was implying. The best advice remains. Don't try and add setup in anything digital. And if you need to dub to an analogue tape, then either get a pro deck or a pro dub house to do it for you. Although I've had pro dub houses muck it up, so you've got to watch them carefully!! Graeme __________________ www.nattress.com - filters for FCP

November 22nd, 2004, 06:19 PM	#19
Graeme Nattress RED Problem Solver Join Date: Sep 2003 Location: Ottawa, Canada Posts: 1,365	For monitoring live you just have to calibrate your monitor to the camera, and all is fine, and you should do this wether setup is added on the analogue outs or not. Essentially setup is a brightness control, so altering the brightness on a monitor is exactly the same electrically as putting in a proc amp and adjusting black level. Graeme __________________ www.nattress.com - filters for FCP

November 22nd, 2004, 01:37 PM	#16
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	<<<-- Originally posted by Graeme Nattress : Greg, Setup is never added to a firewire signal as that is digital and digital never has setup. Graeme -->>> Correction: setup SHOULD never be added to a firewire signal. But unfortunately, on prosumer cameras like the PD150 and DVX, it IS. The proper way for a setup menu item to work would be to only affect the analog output. But if you go into a PD150 and choose setup at 7.5%, it will also change the digital data that goes out the firewire port. Same thing with a DVX. That's a disaster waiting to happen, and should be avoided at all costs. Pro broadcast cameras do it properly: the 7.5 only affects the analog outputs, never the digital recording/output. But on all the prosumer cameras I'm aware of, it affects both the analog and the digital, and that's a problem.

November 22nd, 2004, 04:30 PM	#18
David Lach Major Player Join Date: Oct 2002 Location: Montreal, QC, Canada Posts: 570	So, anybody knows if the XL2 adds the setup to its analogue outputs or not? If it doesn't, my understanding is that blacks will always look crushed when monitoring live (even though the recorded signal will be fine).