Need advice on digital portable capture device

A. J. deLange · April 17th, 2005, 09:24 AM

I've been experimenting with the Traveler this weekend and while I'm still all thumbs with the unit it appears that it's going to work out. I take the RCA audio outputs from the XL2 and put those into 2 channels and the two surround mics into 2 more. The Traveler makes 4 sample synched files on the laptop HD. When video plus camera audio and and 4 audio files from the Traveler are all in FCP I line up the audio direct from the camera with the Traveler's copy of it at which point everything is in sync (all audio and video). I can use the camera's audio for the front if I'm concerned about the A/D - D/A that the audio on the RCAs has gone through or the 4 channels (arranged in stereo pairs) from the laptop if I'm not.

In a 6 minute cut yesterday I found the clocks of the XL2 and the Traveler drifted 1 frame with respect to one another so I'm still interested in syncing the Traveler to the camera. I ordered (or tried to order) a little box which is supposed to convert time code from the LANC port to SMPTE LTC which the Traveler is supposed to accept. If that works I'll be posting again on this subject.

Daniel Patton · May 15th, 2005, 11:09 PM

A. J. deLange...did you ever figure out your sync issue with XL2 and the Traveler?

I am experiencing simular issues with our XL1S and Edirol (Fa101) with roughly 1 to 2 frame audio shift after 4+ minutes of recording.

Anyone?

Douglas Spotted Eagle · May 15th, 2005, 11:13 PM

Only thing I could figure is that the clocking rates are slightly off. The early XL1's had this problem, but I'd assume the XL2 doesn't. I've not worked with the XL2 and an external recorder before. The XL1s does start/stop/sync with the Edirol R4 just fine though, so there is likely a problem in the clock of the recording device, not the cam.

A. J. deLange · May 16th, 2005, 06:22 AM

I know what the problem is - two clocks in two separate pieces of gear with separate crystals ageing at different rates and at different temperatures will run at different rates. That is why they must be synchronized and that's what genlock equipment is for. While the Traveler will accept sync from an external source the XL series of cameras don't supply it in a useable form. What is needed is a simple device that phase locks a 48 kHz sync signal to the horizontal sync pulses in the composite video output of the camera. There is a device which is supposed to take the time code from the LANC port, sync it to the composite video and generate SMPTE time code to which the Traveler is supposed to be able to sync. When I tried to order one of these I was told it was out of stock and so I am waiting for one of these. It's a gamble as I have not been able to verify that the XL2 LANC port puts out time code. The LANC spec says it should but Cannon apparently takes a pretty free hand in their implementation of LANC.

Seems to me that this would be fairly common problem and that wordsync signals should be available from any of these prosumer cameras. Of course I can remember longing for the day when time code would be in them so perhaps my patience will once again be rewarded - eventually. OTOH it seems that MOTU boxes should provide the ability to derive clock from composite video (they do have hardware which does this but I didn't buy a Traveler so I could lug 19" rack mount gear and a 110 V generator around) but this application does not seem to be their major target market.

Alex Filacchione · May 16th, 2005, 06:29 PM

Quote:

Originally Posted by Arne Johnson

Alex, I just got a Mixpad and Hi-MD minidisc recorder based on your recommendations, and am happy with it so far...This may be a dumb question, but if you're going into the Mixpad with a mic, do you go out to the minidisc into its line in or mic port? Seems like Line in sounds better, the mic in is too hot and have to use the minidisc recorder's low sensitivity setting.

Thanks!

Arne

Well, sorry to respond 2 months too late! I just got an email notification 2 days ago that this thread had been responded to. Why I didn't get one 2 months ago, I don't know...

Anyway, you would go into the mini disc via line in.

The difference between mic & line in is that for the mic in there is some sort of a pre-amp to boost the levels of the mic's output since it is so low. A line level input is the same input as the mic, but it bypasses the pre-amp.

Since the mixpad has pre-amps on the XLR connections, the line out of the mixpad should be amplified enough for the line input of the mini disc.

Of course, it doesn't hurt to play around and experiment too!

Alex F

May 15th, 2005, 11:09 PM	#17
Daniel Patton Major Player Join Date: Apr 2005 Location: Knoxville TN Posts: 589	A. J. deLange...did you ever figure out your sync issue with XL2 and the Traveler? I am experiencing simular issues with our XL1S and Edirol (Fa101) with roughly 1 to 2 frame audio shift after 4+ minutes of recording. Anyone? __________________ Our eyes allow us to see the world - The lens allows others to see the world through our eyes. RED ONE #977

May 15th, 2005, 11:13 PM	#18
Douglas Spotted Eagle VASST Join Date: Jan 2004 Location: Stockton, UT Posts: 5,648	Only thing I could figure is that the clocking rates are slightly off. The early XL1's had this problem, but I'd assume the XL2 doesn't. I've not worked with the XL2 and an external recorder before. The XL1s does start/stop/sync with the Edirol R4 just fine though, so there is likely a problem in the clock of the recording device, not the cam. __________________ Douglas Spotted Eagle/Spot Author, producer, composer Certified Sony Vegas Trainer http://www.vasst.com

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April 17th, 2005, 09:24 AM	#16
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	I've been experimenting with the Traveler this weekend and while I'm still all thumbs with the unit it appears that it's going to work out. I take the RCA audio outputs from the XL2 and put those into 2 channels and the two surround mics into 2 more. The Traveler makes 4 sample synched files on the laptop HD. When video plus camera audio and and 4 audio files from the Traveler are all in FCP I line up the audio direct from the camera with the Traveler's copy of it at which point everything is in sync (all audio and video). I can use the camera's audio for the front if I'm concerned about the A/D - D/A that the audio on the RCAs has gone through or the 4 channels (arranged in stereo pairs) from the laptop if I'm not. In a 6 minute cut yesterday I found the clocks of the XL2 and the Traveler drifted 1 frame with respect to one another so I'm still interested in syncing the Traveler to the camera. I ordered (or tried to order) a little box which is supposed to convert time code from the LANC port to SMPTE LTC which the Traveler is supposed to accept. If that works I'll be posting again on this subject.

May 16th, 2005, 06:22 AM	#19
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	I know what the problem is - two clocks in two separate pieces of gear with separate crystals ageing at different rates and at different temperatures will run at different rates. That is why they must be synchronized and that's what genlock equipment is for. While the Traveler will accept sync from an external source the XL series of cameras don't supply it in a useable form. What is needed is a simple device that phase locks a 48 kHz sync signal to the horizontal sync pulses in the composite video output of the camera. There is a device which is supposed to take the time code from the LANC port, sync it to the composite video and generate SMPTE time code to which the Traveler is supposed to be able to sync. When I tried to order one of these I was told it was out of stock and so I am waiting for one of these. It's a gamble as I have not been able to verify that the XL2 LANC port puts out time code. The LANC spec says it should but Cannon apparently takes a pretty free hand in their implementation of LANC. Seems to me that this would be fairly common problem and that wordsync signals should be available from any of these prosumer cameras. Of course I can remember longing for the day when time code would be in them so perhaps my patience will once again be rewarded - eventually. OTOH it seems that MOTU boxes should provide the ability to derive clock from composite video (they do have hardware which does this but I didn't buy a Traveler so I could lug 19" rack mount gear and a 110 V generator around) but this application does not seem to be their major target market.