Or more likely something like, 30 fps and 29.97 fps., which would slowly drift.
Sorry, no. The time stays the same, there are lesser frames in the same time. Thatās all.
Without the knowledge about the real world situation and the files being recorded, all suggestions are speculation.
Such statements are the reason Iām getting upset. This is simply wrong information.
Old QU is not able to sync to external. It is always the sync master.
No, because he wrote:
Thatās why I wrote:
To avoid unnecessarily reducing the quality of the single frames, itās best to preserve every frame during video processing.
Converting from 24 to 25 fps would require re-interpolating each frame in a highly complex process based on its neighboring frames (particularly difficult with hard cuts), which isnāt strictly necessary - or youād end up with jerky images.
Both of these issues can be avoided by simply playing back or edit the 24 fps footage at 25 fps.
And for these reasons, a cinema movie will typically run faster in traditional television.
However, if you recorded audio simultaneously to the 24 fps, it will no longer be synchronized when played back at 25 fps.
But we do not know how much it drifts.
It could be a different word clock source involved. These PLL clock sources are temperature dependent and could have minimal differences. Over a period of time this could make a difference.
To avoid such problems, you need to sync the recording devices to an external clock (not possible with the QU) or record everything audio and video on one device.
Something like a BMD Video Assist, an Atomos Shogun or a computer.
Please read aslo the original post again:
These are unlikely to be āminimal differences over a period of timeā.
Of course, you can invest in professional video equipment, but rest assured that Iāve recorded countless events using also this simple method without any problems.
Okay, sometimes there were discrepancies of one or two tenths of a second in an hour, but something like that can easily be corrected in the audio tracks.
The problem described here is most likely not a technical error or bug.
Have you listened to the Qu recorded audio on its own? Do all the Qu tracks stay in sync with each other? When a Qu USB recording fails, thereās nothing obvious. It just drops samples along the way, without leaving a gap, so the recording gets short. The tracks may end up being different lengths. Iād bet the recording is bad. Approved stick or not, I find the stick recording on these to be completely unreliable.
The QU tracks sounded fine but as you say, a sample here and a sample there, pretty soon it adds up. As far as Iām concerned the feature doesnāt work if it canāt be depended upon.
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Yeah, I always record to a laptop DAW off Qu or SQ. Interestingly, Iāve had good luck with the SD card recorder on my Qu5.
I just encountered the same thing over a three day show on a new Qu-5.
Day 1 and 2 things were syncing up fine. Day 3 I swapped SD cards (different brand and class);and every so often the audio skips quite a bit into the future. I only saw 7 buffer errors when recording to that card so I thought we only dropped 7 samples, but it was multiple seconds at a time.
SD card was the problem. I could also see the ābad cardā cycling when copying to the computer (going faster and slower instead of a consistent transfer rate).
well if theyāre not clocked from the same clock, then itās to be expected that they run out of sync over time.
Within seconds is rather extreme though. Is this a pro level camera?
Yes. Sony XDCAM EX1R.
Itās not the cameras. Itās A&Hās USB recording stack. Known issues.