tc free rec or regen?

[Han Savelkoel]

I used a JVC HD100 to shoot in HDV 25p. Having severe problems capturing and demuxing the stream to a FCP usable. Many data breaks and timecodebreaks appear using Mpeg Streamclip.
Does it have anything to do with the way the timecode is registerd? I think i've used the 'rec' preset. Can anybody tell me the difference between the presets 'free' 'rec' and 'regen'?

[Tim Dashwood]

FREE RUN mode continuously generates TC, even when you turn the camera off. This is useful if you are roughly syncing to a DAT recorder that uses time-of-day stamps, or syncing to other cameras in a multi-cam scenario.
The disadvantage is that you will never ever have unbroken TC over start/stop breaks. The other disadvantage, if you are using time-of-day technique, is that the TC generator will reset from 23:59:59:29 to 00:00:00:00 at midnight, which will confuse all editing systems.
Also, if you are shooting 24P, NDF TC is used and therefore will gradually slip out of sync with time-of-day.


REC mode simply remembers where the TC generator left off when you buttoned off, and then continues generating from that last value the next time you hit the record button. It won't matter where you are positioned on the tape.
The advantage of REC mode is that the TC will never reset to 00:00:00:00 if you review your tape and then accidentally start recording on a blank spot. There will still be a TC "break" but at least it will still continue after the break.
The disadvantage is that you can never truly record continuous TC because the newly recorded value is always based on the value left in the buffer, and not on the tape.


REGEN mode is the most common TC generating (or regenerating) mode used by professsionals. The idea is simply to create a tape with continuous TC without breaks.
When you start recording, the TC reader reads the TC that is already on tape and then regenerates it with frame accuracy to the new recording.
The advantage is obvious, but if you are reviewing your takes often, then make sure you leave lots of post-roll to start new recordings on.
If you start recording on a blank section of tape, the TC reader can't read anything and may just reset to 00:00:00:00. Avoid this at all costs!

[Han Savelkoel]

Originally Posted by Tim Dashwood

When you start recording, the TC reader reads the TC that is already on tape and then regenerates it with frame accuracy to the new recording.

What does this mean for blank tapes? Do i have to write timecode first? How do i manage this?

[Tim Dashwood]

Originally Posted by Han Savelkoel

What does this mean for blank tapes? Do i have to write timecode first? How do i manage this?

No. Just leave lots of post roll after each take (don't button off immediately when the director yells "cut.")
Then, if you review a take, stop the tape in the post-roll area, switch back to camera mode, and the TC will pick up where it left off. This also works with the RET button.