HD to SD conversion problem
by Redžinald Šimek
on
Oct 7, 2008 at 12:40:10 pm
Hi
Program that i edited is HD 1080 50i, and my delivery format is PAL Betacam SP.
For HD editing i work on Kona 3 card, but my SD Betacam PVW series deck is connected on the other suite which runs Blackmagic Multibridge extreme card.
When i export HD file and transfer it on the blackmagic suite, SD output looks terrible with blackmagic realtime downconversion.
I try to nest HD into the 10 bit uncompressed SD sequnce but results are same.
I cannot use kona for realtime downconversion because there is no analog audio output from the card.
What i want to try is to use multibridge extreme as standalone converter between aja and analog betacam deck.
Re: HD to SD conversion problem by walter biscardi on Oct 7, 2008 at 12:47:53 pm
[Redžinald Šimek]"I cannot use kona for realtime downconversion because there is no analog audio output from the card. "
Do you have the K-Box? There is analog audio from there, just go RCA to XLR.
Or pick up a cheap A/D converter like the AJA ADA-4 and go directly into that deck. That outputs 4 channels of analog audio from a digital source.
I don't think the BMD's work like the AJA's with stand-alone conversion. You might be able to do the downconversion through the Kona and connect the SDI output into the BMD and let that pass it through, but we don't use any BMD products here.
Walter Biscardi, Jr.
Biscardi Creative Media HD and SD Production for Broadcast and Independent Productions.
Re: HD to SD conversion problem by Redžinald Šimek on Oct 7, 2008 at 12:56:17 pm
Thanks for fast answer , i know about rca connectors, but do you think that quality from that output is OK for broadcast.
I would buy converter, but i'm now in the pretty tight deadline.
Re: HD to SD conversion problem by Vince Sanchez on Oct 7, 2008 at 5:20:52 pm
You can use the RCA audio outputs to XLRs but don't just use a RCA to XLR cable. That way you're adding over 12db of noise to your signal. It always amazed me that video editors who spend days comparing codecs to get the most pristine picture happily trash their audio and don't hear the difference.
You need to match the levels properly. A +4 input is optimized for that, meaning the lowest noise level will result when you have an input signal that is +4. You need to raise the -10 to +4 in a way that maintains the original signal to noise ratio. We use small boxes designed for that on all our -10 gear. You could get something like that from someone like Markertek. If you have something like a Mackie Mixer with an RCA in and an XLR out (I've used a 1402) you will get a much cleaner signal to the deck. Another issue is an RCA cable, especially a long one is suseptible to picking up hum and an edit suite is full of hum producers. So keep your RCA cable as short as possible and away from video and computer cables.
Thanks,
Vince Sanchez
Intel Quad Mac 2.66
AJA LHe
HD link
OSX 10.4.11
FCP Studio 2
