24 F Jam Sync Out of Sync in Latest Firmware Release at DVinfo.net

Mark Job · December 4th, 2009, 07:29 PM

Hi Mike:
Please be advised the Jam Sync Feature in 24 F looses sync by over 5 seconds in one hour between camera 24 F clock and XDR 24 F clock. I would say the Jam Sync is much more accurate then it was before, and certainly is holding much longer before drift commences, but over 5 seconds in a one hour concert shoot could be disastrous. I will now check Jam Sync at 59.94 i. EDIT: I will repeat the 24 F Jam Sync test to see if my results are repeatable.

Respectfully,

Mike Schell · December 4th, 2009, 08:23 PM

Hi Mark-
Thanks for the feedback, we will check out ASAP and report back.

Best-

Mark Job · December 4th, 2009, 10:23 PM

Hi Mike & Tommy:
OK for Jam Sync @ 59.94 i setting. One hour and a half in perfect sync to the frame as far as I could tell visually. Retesting 24 F Jam Sync to see if malfunction is repeatable.

Mark Job · December 5th, 2009, 12:38 AM

Hi Mike & Tommy:
OK, I've done a repeat test of 24 F Jam Sync, and after 3 hours there is an 8 second drift (Behind) XL H1 24 F TC clock. Test was performed from Jam Sync H1 TC clock in "Free Run" mode. Behaviour of malfunction is as follows....

1. TC Jam Sync locks for about 15 to 20 minutes, then seems to progressively drift to a point of 8 seconds *Slower* than reference TC clock (Camera), then remains more or less consistent at this rate of drift.

2. This anomaly is repeatable.

3. TC rate of drift is considerably less than with the previous firmware release.

Godfrey Kirby · December 5th, 2009, 02:50 AM

I would be cautious about jumping in to blame the 'wandering sync' on the XDR/Nano. It could well be that it's the camera that is going adrift. When using 'time of day' with multiple cameras and seperate audio recorder, we always use Lockit boxes and jam them to the Audio Devices recorder, then mount those on the cameras. Good luck in sorting it out.

Mark Job · December 5th, 2009, 11:12 AM

Hi Godfrey:
I'm not "blaming" I'm reporting. Let's try and keep the passion out of this analysis of the problem as much as possible. Without prejudice, I posed the exact same question about which one could be drifting, and logic dictates if it was the camera, then how do you explain perfect Jam Sync @ 59.94 i ?????

Respectfully,

Aaron Newsome · December 5th, 2009, 12:53 PM

Are both cameras aimed at a time source that they are burning into the recorded picture also?

Mark Job · December 5th, 2009, 01:14 PM

Hi Aaron:
My test criteria was rather primitive. All I did to ascertain what the Jam Sync functions are doing is to place my XDR screen right next to my open XL H1 viewfinder and determine by visual inspection if there is any "drift" in the two clock readouts. When camera and XDR are set to 59.94i there is no discernible drift I can see by visual inspection of the two clocks even after 2 1/2 hours. When the same test is repeated @ the 24 F setting on the XL H1 and 3:2 pull down removal is set on the XDR, as well as TC drop frame carefully enabled on both camera and XDR, then XDR clock begins to drift after approximately 15 minutes and seems to slow down by a factor of 8.5 seconds, then hold at this rate after 4 hours. It is interesting to note that the drift seems to stop its progression at about 8.5 seconds in variance. (???) I don't know why that is. In theory it should continue a slow but steady progressive drift. Perhaps it is possible that the internal processor of the XDR has to do *more* work in performing 3:2 cadence removal, and it is due to this extra processing time - that the XDR clock slows down. (**This is pure speculation on the part of the tester and he has no firm data to back that up - Just a hunch.)

Aaron Newsome · December 5th, 2009, 01:30 PM

Oh I see. Well now I'm extra glad that I don't need to do 3:2 pulldown removal :-)

Dan Keaton · December 5th, 2009, 03:41 PM

Dear Mark,

We appreciate the thorough testing that you are doing.

Mark Job · December 5th, 2009, 07:11 PM

Hi Dan:
You are most welcome Dan and I'm happy to make this product a better one if I can. I like to test stuff out thoroughly before I use it on a shoot. I think CD revisions are moving in the right direction with the 24 F Jam Sync fixes, because the drift is less now. Perhaps the next update will get it bang on. 59.94 i *is* bang on :-) I think this fact makes regular TV shooting in ATSC HD formats with Jam Syncing Perfectly safe and OK with the XDR.

Mark Job · December 5th, 2009, 07:14 PM

Quote:

Originally Posted by Aaron Newsome

Oh I see. Well now I'm extra glad that I don't need to do 3:2 pulldown removal :-)

Aaron: Do you have a Deneke TS-1 or later model electronic Time Code Slate ? If you did, then you could use the TC clock in the slate as a master source and jam both the Nano and your Viper from it (Or do you have an XDR ?). Then you could capture to CF card and we could study the sync versus the Master TC Clock.

Aaron Newsome · December 6th, 2009, 09:37 PM

I'd love to have one of those slates but trust me, I do not own anything to sync TC with at all so I won't be testing this feature anytime soon.

December 4th, 2009, 07:29 PM	#1
Mark Job Trustee Join Date: Sep 2006 Location: Montreal, Quebec, Canada Posts: 1,138	24 F Jam Sync Out of Sync in Latest Firmware Release Hi Mike: Please be advised the Jam Sync Feature in 24 F looses sync by over 5 seconds in one hour between camera 24 F clock and XDR 24 F clock. I would say the Jam Sync is much more accurate then it was before, and certainly is holding much longer before drift commences, but over 5 seconds in a one hour concert shoot could be disastrous. I will now check Jam Sync at 59.94 i. EDIT: I will repeat the 24 F Jam Sync test to see if my results are repeatable. Respectfully,

December 4th, 2009, 08:23 PM	#2
Mike Schell Convergent Design Join Date: Apr 2005 Location: Colorado Springs, CO Posts: 869	Hi Mark- Thanks for the feedback, we will check out ASAP and report back. Best- __________________ Mike Schell Convergent Design

December 4th, 2009, 10:23 PM	#3
Mark Job Trustee Join Date: Sep 2006 Location: Montreal, Quebec, Canada Posts: 1,138	Jam Sync @ 59.94 i Hi Mike & Tommy: OK for Jam Sync @ 59.94 i setting. One hour and a half in perfect sync to the frame as far as I could tell visually. Retesting 24 F Jam Sync to see if malfunction is repeatable.

December 5th, 2009, 12:38 AM	#4
Mark Job Trustee Join Date: Sep 2006 Location: Montreal, Quebec, Canada Posts: 1,138	Second Test of 24 F Jam Sync from Firmware 1.1.151 Hi Mike & Tommy: OK, I've done a repeat test of 24 F Jam Sync, and after 3 hours there is an 8 second drift (Behind) XL H1 24 F TC clock. Test was performed from Jam Sync H1 TC clock in "Free Run" mode. Behaviour of malfunction is as follows.... 1. TC Jam Sync locks for about 15 to 20 minutes, then seems to progressively drift to a point of 8 seconds Slower than reference TC clock (Camera), then remains more or less consistent at this rate of drift. 2. This anomaly is repeatable. 3. TC rate of drift is considerably less than with the previous firmware release.

December 5th, 2009, 02:50 AM	#5
Godfrey Kirby Regular Crew Join Date: Feb 2007 Location: London UK Posts: 71	Wandering Sync..... I would be cautious about jumping in to blame the 'wandering sync' on the XDR/Nano. It could well be that it's the camera that is going adrift. When using 'time of day' with multiple cameras and seperate audio recorder, we always use Lockit boxes and jam them to the Audio Devices recorder, then mount those on the cameras. Good luck in sorting it out.

December 5th, 2009, 11:12 AM	#6
Mark Job Trustee Join Date: Sep 2006 Location: Montreal, Quebec, Canada Posts: 1,138	Wandering Sync Issues Hi Godfrey: I'm not "blaming" I'm reporting. Let's try and keep the passion out of this analysis of the problem as much as possible. Without prejudice, I posed the exact same question about which one could be drifting, and logic dictates if it was the camera, then how do you explain perfect Jam Sync @ 59.94 i ????? Respectfully,

December 5th, 2009, 12:53 PM	#7
Aaron Newsome Major Player Join Date: Jul 2009 Location: Rancho Santa Margarita Posts: 590	Are both cameras aimed at a time source that they are burning into the recorded picture also?

December 5th, 2009, 01:14 PM	#8
Mark Job Trustee Join Date: Sep 2006 Location: Montreal, Quebec, Canada Posts: 1,138	Test Criteria Hi Aaron: My test criteria was rather primitive. All I did to ascertain what the Jam Sync functions are doing is to place my XDR screen right next to my open XL H1 viewfinder and determine by visual inspection if there is any "drift" in the two clock readouts. When camera and XDR are set to 59.94i there is no discernible drift I can see by visual inspection of the two clocks even after 2 1/2 hours. When the same test is repeated @ the 24 F setting on the XL H1 and 3:2 pull down removal is set on the XDR, as well as TC drop frame carefully enabled on both camera and XDR, then XDR clock begins to drift after approximately 15 minutes and seems to slow down by a factor of 8.5 seconds, then hold at this rate after 4 hours. It is interesting to note that the drift seems to stop its progression at about 8.5 seconds in variance. (???) I don't know why that is. In theory it should continue a slow but steady progressive drift. Perhaps it is possible that the internal processor of the XDR has to do more work in performing 3:2 cadence removal, and it is due to this extra processing time - that the XDR clock slows down. (**This is pure speculation on the part of the tester and he has no firm data to back that up - Just a hunch.)

December 5th, 2009, 01:30 PM	#9
Aaron Newsome Major Player Join Date: Jul 2009 Location: Rancho Santa Margarita Posts: 590	Oh I see. Well now I'm extra glad that I don't need to do 3:2 pulldown removal :-)

December 5th, 2009, 03:41 PM	#10
Dan Keaton Inner Circle Join Date: Dec 2002 Location: Augusta Georgia Posts: 5,421	Dear Mark, We appreciate the thorough testing that you are doing. __________________ Dan Keaton Augusta Georgia

December 5th, 2009, 07:11 PM	#11
Mark Job Trustee Join Date: Sep 2006 Location: Montreal, Quebec, Canada Posts: 1,138	Mark The Happy Tester Hi Dan: You are most welcome Dan and I'm happy to make this product a better one if I can. I like to test stuff out thoroughly before I use it on a shoot. I think CD revisions are moving in the right direction with the 24 F Jam Sync fixes, because the drift is less now. Perhaps the next update will get it bang on. 59.94 i is bang on :-) I think this fact makes regular TV shooting in ATSC HD formats with Jam Syncing Perfectly safe and OK with the XDR.

December 6th, 2009, 09:37 PM	#13
Aaron Newsome Major Player Join Date: Jul 2009 Location: Rancho Santa Margarita Posts: 590	I'd love to have one of those slates but trust me, I do not own anything to sync TC with at all so I won't be testing this feature anytime soon.