FORUMS: list search recent posts

"Black frame issue during capture"

COW Forums : AJA Video Systems

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Tjenno Bridges
"Black frame issue during capture"
on Sep 3, 2009 at 3:25:07 pm

Hi there,

We are experiencing a peculiar "black frame issue during capture".
In about 40% of our HD captures we get one black frame at 00:00:40:09. (with two exceptions (see below) the "black frame" is always at this exact timecode).

This means that each time we capture a clip we have to check whether or not there is a black frame at 00:00:40:09 (or at around 00:00:42:00). If yes, then we have to re-capture. Usually the recapture does not have the black frame).

(fyi: We tried cutting the black frame in the timeline in FCP but this produced a picture jump. This means that the "black frame issue during capture" is not an added black frame, but a frame of captured video that was replaced by a black frame.)

And in two occasions we got 2 (and 3) black frames at around 00:00:42:00 (the second black frame contained a dimmed distorted frame from 00:00:04:00 of the same clip.



Our configuration is:

MAC PRO
Processor: 2x3 Ghz Quad Core Intel Xeon
L2 Cache (per processor): 12MB
Memory: 16GB 800 Mhz DDR2 FB-DIMM

OS X 10.5.6
Quicktime Pro 7.6

Final Cut Pro 6.0.5

AJA KONA 3 capture card
- (codecs used = AJA KONA 3: 1080psf 23.98 8-bit)
- (codecs used = AJA KONA 3: 1080psf 24 8-bit)
AJA KONA control panel 5.0

STORAGE:
PROMISE RAID Storage system VTRAK E610f - (6,2TB storage space)

CAPTURING HD via SDI from SONY HDCAM-SR SRW-5500



Looking forward to your replies,
With kind regards,
Tjenno Bridges
- - - - - - - - - - - - - - -


Return to posts index

Jeremy Garchow
Re: "Black frame issue during capture"
on Sep 3, 2009 at 4:55:06 pm

[Tjenno Bridges] "AJA KONA control panel 5.0 "

I'd try updating the drivers as they are now up to version 7. The drivers you have loaded now are from december 2007.

First you need to UNINSTALL the AJA drivers from the AJA Uninstaller Utility. Then restart the computer.

Then reinstall the new drivers v7 NDD if you don't use Shake, and restart.

Jeremy


Return to posts index

Tjenno Bridges
Re: "Black frame issue during capture"
on Sep 4, 2009 at 11:57:53 am

Hi,

Thanks for the quick reply.

Here is an UPDATE:
We haven't installed any new drivers/firmware yet
We wanted to do some more tests first... and we have now discovered that it is Cinema Tools that causes the black frame...

We captured 5 clips, then checked each clip. (they were fine: no black frame at 00:00:40:09)
Then we used Cinema Tools to conform the frame-rate of these clips from 23.98fps to 25fps)

And ... the black frame appeared in 4 out of five clips.
We have Cinema Tools 4.0.1 (as part of Final Cut Pro 6.0.5, which in turn is part of Final Cut Studio 2)

We checked Apple's Webstore and found that there's a new(er) version (4.5) of Cinema Tools.
However this version only comes as part of a new Final Cut Pro 7 upgrade.

Is there a way to resolve this problem without purchasing an (expensive) upgrade ?

Looking forward to your replies.

With kind regards,
Tjenno Bridges
- - - - - - - - - -


Return to posts index


Jeremy Garchow
Re: "Black frame issue during capture"
on Sep 4, 2009 at 4:04:50 pm

[Tjenno Bridges] "Is there a way to resolve this problem without purchasing an (expensive) upgrade ? "

The upgrade is not that expensive, $299 US. But I understand, if you don't want to pay, you don't want to pay.

You can take the file to compressor and conform the file to 25 there. In the encoder tab make sure you set the frame rate to 25, and then in the frame control tab under the retiming section, check the option 'so source frames play at 25.00 fps". That will do a conform, and you won't get the audio speed up. You also have to setup the proper codec and frame size, but hopefully you can figure that one out. If not, post back.

Jeremy



Return to posts index

gary adcock
Re: "Black frame issue during capture"
on Sep 4, 2009 at 9:47:16 pm

[Tjenno Bridges] "we have now discovered that it is Cinema Tools that causes the black frame... "

how?

with a 23.98 > 25 conform the only thing the CT is doing is telling the QT file to play faster- it is NOT adding any frames (pulldown) so I do not know how this could happen.

I checked with one of the guys that works on CT and he told me that it was not possible for a simple conform in Cinema tools to add frames to a file.

maybe you should walk step by step thru your workflow.



gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows for the Digitally Inclined
Chicago, IL


http://library.creativecow.net/articles/adcock_gary/AJAIOHD.php




Return to posts index

Tjenno Bridges
Re: "Black frame issue during capture"
on Sep 7, 2009 at 9:19:15 am

Hi Gary,

Thanks again for the quick reply.
Yes indeed... we do not understand how a simple conform can add black frames.

Then we googled for "black frames" + "cinema tools" and found the following link on the Apple - Support forum:
http://discussions.apple.com/thread.jspa?threadID=1449687&tstart=60

Seems that we're not the only ones with this "black frame issue after conforming in Cinema Tools"
Maybe you could ask your acquaintances at Cinema Tools to investigate this.

With kind regards,
Tjenno Bridges
- - - - - - - - - -


Return to posts index

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