jit.qt.grab with capture delay in snow leopard

spierala's icon

Hello,

I capture 720p 50 with a blackmagic card. When I try to capture the video via the write command I have a delay of nearly 2 secs until the capture actually starts (on a Mac Pro with 10.6, 2x2,93 Quad Core Intel Xeon)

I did not have that prob on another mac pro with with 10.5 on it, a bit lower processor speed but with a RAID system. Do you think it´s because of the RAID or does MAX simply prefer Quicktime 7 (of Leopard) over Quicktime X (of Snow Leopard).

Many thanx,
Florian

wiccy's icon

i got the same problem everytime i use an external camera for capturing, but not on the built-in camera. maybe it has something to do with this.

spierala's icon

hello all,

@wiccy: what kind of mac do you have?

i just downgraded the "delay mac" to 10.5.8 and quicktime 7.6.6. So the main software is equal to the "no delay mac". But the delay is still there.

The delay mac has 32 GB of Ram and is the fastest machine available.
Is it possible there is too much Ram? Or too fast?

I think the Hardware-RAID system can´t be the reason cause a RAID is not necessarily faster.

mhh,
florian

spierala's icon

heee,
we switched now to a mac 2,8 Ghz Quad Core Intel Xeon. That generation (Early 2008) has no delay at all. The new Mac had delay also after driver update and firmware update of the Blackmagic Card.
florian

walker's icon

dear florian,

what sort of capture blackmagic card are you using exactly?

do you have latency while capturing hd signal and downgrading it via hardware (I only mean the stream display - without recording)?

best

dario

PEL's icon

Any response to this question? I have the same delay problem!

I'm using a MacBookPro 2.66 with 4Gb

Jonas's icon

Still having the same problem on a MacBook Pro, Late 2007 with 2.2 Ghz and 4 GB of RAM, running OS X 10.6.8 and QuickTime 10.0.

Additionally when I open the recorded .mov in Quicktime and look at the movie information, I see that it has strange framerates like 14.57 and the video is stuttering and incomplete. (Although I send the write message with, say 25. as framerate setting!)