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Audio dropouts on Kona 3 to DigiBeta

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Malcolm Dyer
Audio dropouts on Kona 3 to DigiBeta
on Mar 2, 2009 at 6:45:46 am

Hello
I am in PAL land with a late 2008 MacPro 2.8GHz 8 core with 4GB RAM.
My client is supplying ProRes 1080i50 files on HDD to play to DigiBeta (DVW-500P or DVW-A500P).
I am copying the files to the Video drive (2x 1TB in Raid 0) before attempting to Edit to Tape.
I am not currently using an external reference for the Kona 3 card and DigiBeta.
When I Edit to tape it appears to run OK for about 10 mins and then I start getting two issues.
Sometimes but not every time I get attacks of sparkles (pixel blocks) at various intervals. Surprisingly there is no evidence of these recording on the tape even though I see them on the SDI output of the DigiBeta through a Black Magic SDI-HDMI converter. This is the lessor of my problems but does not inspire confidence in the client if he sees it.

The main issue is random audio dropouts on the DigiBeta recording even when using brand new tape. These usually start appearing after 10 mins.
I thought it was a problem with the DVW-500P but I have had it serviced and it still does it showing Audio channel condition errors on Confidence replay during Record as well as on normal replay.
I switched to the DVW-A500P and watched the recording in Confidence with no errors that I could see but when I replayed the tape I had random audio dropouts.
I can not afford to have any more tapes rejected.

Would using an external reference make any difference? I have Black/Burst from a Leitch SPG available.
Now that I have experienced this on both machines I am starting to feel it is not a VTR issue. They appear to work OK in other situations.
Is there anything else I may be doing wrong?
Thanks
Malcolm

PMW-EX1
HVR-A1P
Vegas 8 Pro
MacPro/Final Cut Studio 2


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Aaron Neitz
Re: Audio dropouts on Kona 3 to DigiBeta
on Mar 2, 2009 at 5:39:45 pm

Couple things

1) so you're monitoring your digitbeta with an LCD hooked up with SDI/HDMI converter? The converter is suspect... I've seen "sparkles" with an HDMI converter myself. Typically it was due to illegal video levels freaking the converter out.

2) is your deck in "input video" reference?

3) are you recording audio over the SDI line or AES?



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Malcolm Dyer
Re: Audio dropouts on Kona 3 to DigiBeta
on Mar 3, 2009 at 3:04:20 am

Hello Aaron
Thank you for the reply.
1. I tried monitoring Video 1 out and got sparkles on that as well. They seem to be generated in the DigiBeta but they do not record on tape.
2. No, it is on REF. I am now supplying Colour Back to both the DigiBeta and Kona card.
3. Audio is being recorded from SDI. I have not tried AES but I guess I should try it.

I did one pass this morning with a new tape and a reference. It played back perfectly on both machines but I have not been able to repeat the feat although I am reusing tapes.
Thanks
Malcolm

PMW-EX1
HVR-A1P
Vegas 8 Pro
MacPro/Final Cut Studio 2


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Bob Zelin
Re: Audio dropouts on Kona 3 to DigiBeta
on Mar 4, 2009 at 1:14:54 pm

Malcolm,
you did the right thing by hooking up your Leitch black generator.
You also must remember to go to the AJA Control Panel, and select EXT REF in the control tab, or the Kona will not accept the Leitch black signal (you probably know this). If you don't use a black gen to genlock your Digi Beta, you will ultimately get more than "audio dropouts". You will see increasing "channel error condition" lights on your Digi Beta VTR, and about 15 - 30 minutes into your "edit to tape" output, your audio will seem to totally disappear. You will hear the servo motor in the digi beta start to "warble",and you will get servo error lights as well as channel condition error lights on the digi beta.

Always use your Leitch black generator. There is no trick to avoid using this.

BobZelin




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Malcolm Dyer
Re: Audio dropouts on Kona 3 to DigiBeta
on Mar 4, 2009 at 10:29:11 pm

Thank you, thank you, thank you Bob
I think I owe you a packet of cookies.
I nearly went out of my mind over this.

I had looped the reference through the DigiBeta to the Kona but did not discover the Control Panel setting though I had looked for one.
The symptoms were as you described occurring after 10-15 mins.
They included crackling audio and sparkling video out of the DigiBeta and steadily worsening channel condition errors.
A very few recordings worked ok but most had errors especially when played back on another machine.
A lesson learnt the hard way.
Thanks
Malcolm

PMW-EX1
HVR-A1P
Vegas 8 Pro
MacPro/Final Cut Studio 2


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gary adcock
Re: Audio dropouts on Kona 3 to DigiBeta
on Mar 3, 2009 at 2:25:37 pm

[Malcolm Dyer] "Surprisingly there is no evidence of these recording on the tape even though I see them on the SDI output of the DigiBeta through a Black Magic SDI-HDMI converter. "



this is a sign of a bad converter.
what does the HDSDI look like without the converter?



gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
http://library.creativecow.net/articles/adcock_gary/AJAIOHD.php




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Malcolm Dyer
Re: Audio dropouts on Kona 3 to DigiBeta
on Mar 4, 2009 at 10:17:35 pm

Hello Gary
THe sparkles were visible on composite video out of the DigiBeta as well. It appears that all my issues were down to the lack of a reference. See my reply to Bob.
Thanks
Malcolm

PMW-EX1
HVR-A1P
Vegas 8 Pro
MacPro/Final Cut Studio 2


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