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amira timecode oddness

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rich   

an Amira timecode question.
Film I am on at the minute, the DIT tells me that a few takes a day are 40 seconds to a minute out of sync, whilst everything else is absolutely fine.
he can see no pattern to which takes will be out of sync, and it may be take 3 and 4 that is out, and take 5 is fine. 
Have ruled out the cards camera is recording to as it happens across all 4 cards that they are using.

I am using a 788T fed into a Zaxcom cameralink, which transmits to the ERX receiver permanently attached to camera. everything set to 24fps. and i dont believe that camera has gone off speed yet on this film.
I believe that the settings on camera are correct and on the ERX. The camera certainly picks up timecode as soon as the box is plugged in.
and the camera is very rarely out of range of the zaxnet signal for long enough to drift. though 40 seconds doesnt really seem like drift, more like a massive error somewhere.

my only thought of what to try is to use lockit box, but as i dont own one, would prefer to try and get the camera rental company to provide one to see if that solves the issue. though after speaking to the DIT, he is saying that as long as its only a few takes a day, he can manage with it. but if it gets worse, he will have a word with the money people to see if they can get a lockit for a few days to see if that cures it. I will happily buy a lockit if that cures the issue, but dont want to spend the money if it turns out to be a camera issue.

the thought occurs that we have 2 cameras in today for a big fight scene, so will be keeping an eye out in case the cameras both have this issue on the same take.

but the point of this long winded explanation was to see if anyone else had experienced the same thing.

thanks

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My take on this is you really need to get a lock box of some sort (Denecke, Ambient, Mozegear, Betso, Tentacle) and substitute for the ERX. If the problem persists it will be fairly certain confirmation that the problem is happening somewhere else down the chain. Substitution is the core part of any troubleshooting routine so you should try and get your hands on a standard sync box.

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I agree re: troubleshooting.

Meanwhile, is the ERX set to automatically detect the incoming time code rate?  Maybe set it to the rate manually and see if that makes a difference. I'm not basing this on anything other than looking for possibilities .

Of course, this might be a camera glitch.  As Jeff said, a standard sync box could help deduce that.

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I noticed similar behavior recently caused by an intermittent connection. This was using lockits on the camera, and random takes would be 5-10 minutes behind on one camera.

  Running tod the amira seems to reset to it's system time instead of 0's like the alexa does when code is lost.  Try a day with your tc values starting at 1 hour, and see if it is still 40 sec off, or if it jumps to tod then back.  If it does, it could be an intermittent connection, etc.

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My take on this is you really need to get a lock box of some sort (Denecke, Ambient, Mozegear, Betso, Tentacle) and substitute for the ERX. If the problem persists it will be fairly certain confirmation that the problem is happening somewhere else down the chain. Substitution is the core part of any troubleshooting routine so you should try and get your hands on a standard sync box.

+1 on the A/B test.

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I am surprised that two ardent Zaxcom supporters would recommend to start troubleshooting with the ERX. While I would agree that the ERX is one of the components that should be part of troubleshooting, I would not rate it the top most likely culprit that should be checked first. Cables and cameras (incl. its settings) are far more likely to be the cause for this, I think. 

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I just assumed that physical connections, cables, etc., had been ruled out --- this would be standard procedure. Regardless of being an "ardent Zaxcom supporter", I think that substituting a different timecode device is the easiest, fastest and most efficient way to proceed with troubleshooting. I think even those that use the ERX everyday, day after day, might suggest the same substitution.

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rich   

trying a traditional sync box was one of my first thoughts, but budget has prevented me from doing so so far.

i do not own any, and am not prepared at this point to pay for the hire myself of a sync box when i am not 100% sure that this is the issue. and whist the DIT is saying it is not an issue he cant easily deal with, I have no leverage with production to get the camera hire company to provide one.

 

today was a 2 camera day, and i tried setting the TC voltage to 2.0v, rather than the standard 1.0v, so will speak to the DIT in the morning and see if anything was better. and if the 2 cameras show issues for the same take.

 

the right angle minijack connector is taped in on any receivers now, as i did have an issue one day where the connector was not properly fitted. auto frame rate detection has also been turned off from today as well.

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I'm currently on a Feature in South Africa and we're having the same issue. Between DIT, rental house and ARRI, they've confirmed its a firmware bug. What seems to be happening is the camera is randomly reverting to its internal clock. This is irrespective of whether you have a time code source attached to camera or not. We're shooting on two Amira's and a Alexa Mini. I've been using my brand new Tentacles, which are fantastic btw, so this threw me for a loop, immediately thinking it was a Tentacle issue. However as I said ARRI have confirmed the bug in correspondence with Rental house. The Alexa mini does not have any issues much like it's bulletproof bigger brother.  

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 It still amazes me that Arri is now in its third generation of camera, and we still have to stick a time code box on it to maintain sync.  It should maintain proper time code with battery changes, speed changes, etc. It can't be that hard.

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I've worked on Arri Alexa's for years without having to use sync boxes. I jam directly from 788T and good to go. Jam again at lunch, no issues. The Amira is new camera and in my research learnt that it had different clock and it was recommended to use sync box. It's unfortunate that the firmware has a bug but I'm sure it'll be sorted out very soon.

Sent from my iPhone using Tapatalk

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today was a 2 camera day, and i tried setting the TC voltage to 2.0v, rather than the standard 1.0v, so will speak to the DIT in the morning and see if anything was better. and if the 2 cameras show issues for the same take.

Any update? 

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rich   

nothing any better alas.

though Ivan's post tells me that Arri are aware that it is a firmware issue.

i will try and get a chance to see what the cameras internal clock is set to. and see if it is about 40 seconds off my 788s clock.

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Here is excerpt from correspondence between Rental House and Arri.

'In the current SUP 2.0.14 is a bug related to the symptoms you explained to us, we have been able to reproduce this here in Munich.

Our engineers are working on a fix for this with high pressure already.

From the point of now we don’t know when a fix will be ready or if it will be implemented in the next SUP release.

Sorry for not having better news at the moment, and the inconvenience caused from our side.'

Sent from my iPhone using Tapatalk

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So are you saying that at the moment Amira timecode can't be relied on even with a sync box, as it resets to system time at random? This would explain some problems I had recently, but I put it down to a mistake somewhere in the process. 

This only happened when I synced the Amira to my 664's clock, but not the other way round (although this was only two days, so difficult to diagnose conclusively)

If the system clock has timecode level accuracy then that would give a workaround of jamming recorder to camera until a fix is issued, but only work with one camera. 

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rich   

today i set both cameras system clock to be as close as i could manage to my timecode clock, so will hear from the DIT in the morning if that has affected the sync.

i am hoping that if the issue is because the camera - at some random point - jumps to its internal clock, the sync should difference should be much less, and also prove that this is the same issue that Ivan has identified.

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anyone have any update with what tc workflow is working with the Amira?

On the Arri website current firmware seems to still be 2.0.14 13807 which hasn't been updated since 30th March 2015.

I have a shoot tomorrow with a couple of Amiras, I'll set system clock as rich suggests, erx's and cross my fingers I guess

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how about setting the Amira's system clock to a value way off actual time? That way if it jumps to internal it will show a TC value that's WAY off and therefore noticed more easily than an offset of only a few seconds.

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That's pretty much what I did one m

Sent from my iPad using Tapatalk

Sorry my keyboard wonky on my iPad since screen change. I set codes about 10mins apart so jump was obvious. Our post facility would then manually sync the few out clips.

Sent from my iPad using Tapatalk

I'm going to follow up with rental house tomorrow to see if any bug fix imminent or done.

Sent from my iPad using Tapatalk

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Andy P   

I'm currently on a job with an Amira, shooting at 29.97 DF. The Amira will accept incoming code from an ERX but it is clearly out of sync. We shot a few files with a digislate and checked them in Resolve. They were out by between 1 and 3 seconds, so not constant. It was also out when I hardwired  my Nomad TC straight into the Amira. But it looked to be correct when it was in 29.97NDF and 25fps. So the first half day we shot with the understanding Post would have to sync up using the board. At lunch we phoned Arri and were told it's a known issue that the Amira "doesn't like" DF frame rates, and they're working on a fix. 

After lunch I tried jamming the Nomad from the Amira as often as I could. I'd then also have to rejam the slate. It looked to be ok. We heard from Post the next day that once synced, the files stayed in sync and didn't drift, which I was concerned about, and also that the files from after lunch were autosyncable, ( so Amira as a master and Nomad jammed from it). We continued for a couple of days with this awkward procedure but then on the fourth day I could see the code was slipping again when I was rejamming, with the Amira's clock running faster than the Nomad's, so they had to use the board to sync again. 

Looks like there's a bit of work needed on the Amira's timecode functions..

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