FORUMS: list search recent posts

Do I need a Black Burst gen?

COW Forums : AJA Video Systems

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
thebishop
Do I need a Black Burst gen?
on Mar 29, 2007 at 5:35:14 pm

I am setting up a Final Cut Pro editing system and I'm trying to determine if I need a reference signal or black burst generator. Under what circumstances is one necessary? And, what would be plugged into "loop" on the back of the IO?

I have (2) Sony DSR-1500 DVCAM decks and a DVD player that will route to the IO.

Firewire from the IO to the computer.

Thanks for your help.


Return to posts index

Bob Zelin
Re: Do I need a Black Burst gen?
on Mar 29, 2007 at 7:54:54 pm

A black burst generator is the reference signal. If you wish to not get vertical bars in your video, wish to keep everything locked to a single reference, you should purchase a black generator. A cheap solution is the Horita BSG-50 (not the BG50). If you choose this model, make sure to purchase a 75 ohm BNC terminator to put on the looping input of your AJA I/O Reference input, or the Horita box will appear to do nothing.

When you use your DVD player as a source, this is not a genlockable source, so you would switch the AJA Pro I/O Control Panel to Free Run instead of EXT REF in this one situation. You have a lot of sources (2 DSR1500 and one DVD, and I bet you have more) - so you might consider getting a patch panel as well.

Bob Zelin


Return to posts index

thebishop
Re: Do I need a Black Burst gen?
on Mar 29, 2007 at 8:23:23 pm

Currently, when I'm laying to tape, I'm not getting any distortion in the video. However, I am getting some digital junk and jumpiness in the image when dubbing from deck to deck (I'm currently going through an old SDI switch, so I'm about to try patching straight in to see if that fixes it).

What I suppose I don't understand is, what is the BB Gen doing? Would I plug it into the REF IN on the deck or the LOOP on the IO?


Return to posts index


Bob Zelin
Re: Do I need a Black Burst gen?
on Mar 29, 2007 at 8:52:04 pm

I assume you are dubbing using analog component. Is this correct? The DSR1500 does not offer seperate analog composite and analog component outputs - it uses the same jacks for both, which you select via the menus. So you dont' have a "spare" video output to feed the REF VID IN of your record VTR. Your jumpiness will disappear if you have a black generator to lock the VTRs together.

I mean no offense, but this is not Video 101, where you learn exactly how reference signals or genlock signals work. The color black signal is called a composite video signal, and one of the pulses "composited" into this signal is horizontal sync and vertical sync. These pulse signals are used to synchronize or "genlock" (lock to generator) different pieces of equipment, that are meant to be used together. Some VTR's have switches on them, that allow the VTR to derive the synchronization signal from the video input of the VTR (where it strips off the sync signal from the composite video input).

I don't want to take this further, but buy a black generator, and save yourself some aggrivation. You plug it into the Reference IN, and you will TERMINATE the other BNC connector with a 75 ohm BNC connector. You will take the other outputs of your black generator, and stick them into the REF VID inputs of your VTR's.

Bob Zelin


Return to posts index

thebishop
Re: Do I need a Black Burst gen?
on Mar 30, 2007 at 12:17:35 am

This answers my question completely. Thank you for a thorough response.


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]