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Hey Bob! - Genlock Question

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Aujom Productions
Hey Bob! - Genlock Question
on Sep 29, 2006 at 5:01:37 am

Before you lose it and shove a BSG-50 up my $&*@!, riddle me this...

I just replaced my old editing Mac (capturing w/ BM decklink SP) with a new one (using an LHe). I used to loop the Y output of my old card through the REF IN on my Beta deck (PVM-2800), then to the Y component in. It worked fine for years. Why won't that same wiring work with the LHe? I've been messing with it for a while. Tried freerun in the control panel. Nothing. What am I doing wrong? Besides not having a BSG-50...



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Bob Zelin
Re: Hey Bob! - Genlock Question
on Sep 29, 2006 at 1:11:26 pm

This "looping the Y into the Ref IN of the 1800" trick, is a trick that Grant Petty came up with. Now Grant knows more about most things than I will ever dream of knowing, but he is WRONG about this technique. The original mindset for the Decklink card, was that it locked to the SDI Input video, and did not require a Genlock signal, and this was a big push for Blackmagic for a long time - that you don't need genlock, because the card locks to input video. Well, this is NONSENSE (except for SDI and HD-SDI signals) - and in my opinion, Grant was wrong about this technique, and since those days, Blackmagic cards all have Genlock on them now. The Beta 1800 wants to see a signal going into both it's Video Input and Reference Input, and when you put the VTR into play, a signal comes out of the Y output (a B+W composite video signal with no burst on it), and this can "fool" the Beta 1800 into thinking it's got a reference signal, but you still get into trouble , and you still get all the error messages.

When you say "hey, I got it to work" - well, I get AJA I/O boxes to work sometimes with other FW400 devices on the native FW buss, but ITS WRONG, and I EXPECT PROBLEMS when I do it. I can "jury rig" 23.98 systems to work without a Tri Level Sync generator, by disconnecting all reference inputs, and forcing the system to lock to input video, but ITS THE WRONG THING TO DO. I can get a horrible VHS machine to record onto a Beta VTR, by looping the composite video signal into both the Video and Reference inputs of the Beta VTR, so it tracks the reference with the unstable input - avoiding a TBC - BUT ITS THE WRONG THING TO DO, and you have to be a MORON to work this way on a regular basis, if you make your living this way. These techniques, and others, are teriffic in an emergency, but if you make your living doing this, you can afford $300 for a black generator, $300 for a TBC (not needed with an AJA I/O product), and the few bucks required to do most of what we need to do, to make a living.

This ain't a hobby - you feed your family with this stuff. I can use a sponge to paint a room - why buy a paintbrush or roller. But you'd have to be crazy to do this if you were a professional painter.

You own an $8000 VTR, a $4000 computer, a $1500 capture card, probably lots of other great pro gear, you can afford the $300 (or less on ebay) to get a black gen.

Bob Zelin


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Bob Zelin
Re: Hey Bob! - Genlock Question
on Sep 29, 2006 at 1:21:59 pm

Hi Brian -

I just saw that you also own an Apple XServe RAID, which is the most expensive storage array on the market, so I really don't want to hear that you can't afford a black gen.

Bob Zelin


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Aujom Productions
Re: Hey Bob! - Genlock Question
on Sep 29, 2006 at 4:27:23 pm

Thanks a lot for the advice Bob! A friend of mine down the street has a setup very similar to mine and swears by his tri-level sync generator (Evertz 7750SRG-HD I think). You mentioned such a device in your reply...do I need one? It sounds like this is necessary for HD work (which we will be doing very soon) and it would make the BSG-50 unnecessary. Is that correct?

I've been using a Canopus ADVC-100 for "oddball" analog ingest (VHS, random consumer camcorders, etc.) for the past 4 years, works fine. Specifically, how would the TBC help me? I apologize for my ignorance on a lot of the technical fundamentals...that's why I'm coming to the mountain...

Also, I want to monitor my Kona video output on my Sony PVM-20L5 using component in. Currently I'm using composite in looped through the Beta (PVM-2800). Obviously not great. I think the best way to do this is use an SDI to Component converter on one of the SDI outs from the Kona. Do you agree and if so, can you suggest the best VALUE converter. Yes, you're absolutely right, we do have a lot of great (EXPENSIVE!!!) gear here and I've busted my ass to make it happen. My questions are a combination of ignorance of the minute/vast technical issues associated with our line of work and the aching desire to NOT WASTE MONEY on very expensive gear!!

Thanks again for ALL your HELP!!!! Brian



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Bob Zelin
Re: Hey Bob! - Genlock Question
on Sep 30, 2006 at 2:05:59 pm

Hi -
unless you are working in the feature film industry, and do film print release, you do not need the Evertz Tri LEvel Sync gen. There are different philosophy's on this, but I do not see any need for anyone finishing for Television release to work at 23.98 native frame rate. You shoot at 23.98 (or 59.94 or 29.97), and let the VTR do the 2:3 pulldown for you, so your HD projects are all at normal frame rate (you still get the film look with no aggrivation of editing at 24p). For this, you need nothing other than the generic cheapo black generator - not a $4000 Evertz. However, if you need to print back to 24p for film release, you need a product like this. Most people just need a cheapo black generator.

As for the Sony monitor - simply purchase the AJA K Box or K3 box - it's $299, and has the analog Out Y Pb Pr on it, to feed your PVM-20L5 an analog HD signal, which looks GREAT. You don't need anything else.

Bob Zelin


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Robert Broussard
Re: Hey Bob! - Genlock Question
on Sep 30, 2006 at 5:14:41 am

v[Aujom Productions] "Before you lose it and shove a BSG-50 up my $&*@!, riddle me this..."

LOL... God, I love the way you put that!

Robert


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