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Arri Amira


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I've heard that the angle of the 5 pin XLR isn't the same as the Alexa, and those of us that have the 90 degree connector facing up (Remote audio umbilical), won't work on the Amira. 

 

Anyone confirm this?

If it's a Peter Engh camera-end, the 5-pin XLR works and it physically fits the Amira.  The problem is the 90 degree 5-pin is at 12 o'clock, and covers the 3.5mm monitor jack.  The Neutrik 3.5mm 90 degree plug won't fit underneath the XLR.  But, the 5-pin XLR is easily rotated to 2 o'clock (no re-soldering). 

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Glad its not just me then!

What I found surprising is that the more recent firmware introduces this lack of headroom.

I contacted Arri support about this and they supplied a small post from the engineers in Germany:

"The observation is correct, the available attenuation factor was reduced between the two software packages.

We did this because the camera does in fact only accept levels up to +8dBu. This is a limitation of the current hardware design.

 

SUP 1.0.06 indeed offered to set -18dB through the user interface but the actual attenuation available in the analog part before the DSP is only -6dB, the remaining was attenuated in the digital domain. This left users with the impression that they could safely input 24dBu while the signal in fact was already clipping. If the recording wasn’t properly monitored, the chance of bad results was rather likely to occur.

 

The current setting with SUP 1.0.11/1.0.15 represents the options more accurately. If you intend to feed 24dBu line level into the camera you will need to use a physical attenuator to make sure clipping won’t occur. For 8dBu input level an attenuation factor of -6dB has to be set in the UI to avoid clipping. 0dBu line level leaves you with 8dB headroom."

 

So my interpretation of this is that the choice/design of the hardware was rather poorly conceived and so they are having to compensate via a software/firmware solution.

 

Something for everyone to be aware of. I can't see it changing as it is a hardware problem.

When I worked with an Amira I sent line-level tone from a 302 to the camera, and with the camera's gain knobs turned all the way down the meters showed -9dB.  (I have my peak limiter set at +4dB, so any spike would never go above -5dB on the camera.)  I listened to a miced voice on the camera headphone output and it sounded great.  Very clean.  So, I don't get the concern about too little cushion.  What am I missing?  Also, the Arri engineers said the Amira "accepts levels up to +8dBu."  If I'm understanding that correctly, clipping doesn't start until +8 on the Amira?  In my case, that would give me 13dB of cushion.  Why would I need to set camera level at -18db and lose another 9dB of dynamic range? 

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Why would I need to set camera level at -18db and lose another 9dB of dynamic range? 

  

In practical terms, you're not losing any dynamic range but just adjusting where within that range your nominal mix level is.  Dynamic range is the difference between the highest signal a circuit can handle and the noise floor (the lowest).  Changing your nominal level doesn't alter that, it just changes how much headroom you have for signal peaks above your nominal level.

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In practical terms, you're not losing any dynamic range but just adjusting where within that range your nominal mix level is.  Dynamic range is the difference between the highest signal a circuit can handle and the noise floor (the lowest).  Changing your nominal level doesn't alter that, it just changes how much headroom you have for signal peaks above your nominal level.

But, I mix to peak at the nominal level.  (Doesn't everyone?)  If I reduce the nominal level from 0dB ("the highest signal a circuit can handle") to -20dB, I've effectively reduced the dynamic range of the recording by 20dB.

 

Another consideration is post production.  If the level of the audio files is too low they have to crank gain all the way, adding noise (depending on the quality of their preamps).  So, to me, setting the nominal level lower than necessary is a double whammy: less dynamic range and degraded S/N. 

 

Getting back to me original remarks, I still don't see what the issue is with line level feeding the Amira, why anyone is getting "crunch" if they are below 0dB (or +8dB according to the Arri engineer), and why Arri would have to send someone to the U.S. to fix anything.

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Amira TC issue

664 to acl204 , allgood.

Plug into Amira with TC and Sync cables

No jam!!!

The menu is set to Free run , Regen ,

Tell me what I did wrong

Used the same acl 204 to jam an Alexa. ( different process i know)

Not a major as I have audio in to the camera and we can get a TC slate  on everything but I'd still like to know!

Cheers

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Amira TC issue

664 to acl204 , allgood.

Plug into Amira with TC and Sync cables

No jam!!!

The menu is set to Free run , Regen ,

Tell me what I did wrong

Used the same acl 204 to jam an Alexa. ( different process i know)

Not a major as I have audio in to the camera and we can get a TC slate  on everything but I'd still like to know!

Cheers

I had the same problems with the Amira this week using my Nomad and an ERX. We were eventually able to get it to work, but it wasn't just connect and go.  These might be obvious answers, but if we cycled the camera's TC BNC mode to off and then back on that seemed to fix it...sometimes. Can you adjust the acl204's voltage out?  I turned the ERX up to 1v out which seemed to help. I can usually get away with .5v or less.  It was definitely finicky. One time the cameraman had changed to a high speed framerate and forgot to go back to 23.98. Make sure your framerates match. 

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Make sure your framerates match.

This is key, of course. There is the sensor's and the project's framerate to consider. They must match, of course.

Also, similar to the recent thread here about the Maxx TC, the Amira has only one BNC for TC and it must be set to "TC In" for external TC.

I have just finished a months project shooting with the Amira. I have used my older Ambient ACL293 (?, the red one) and it worked without any issues

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Amira TC issue

664 to acl204 , allgood.

Plug into Amira with TC and Sync cables

No jam!!!

The menu is set to Free run , Regen ,

Tell me what I did wrong

Used the same acl 204 to jam an Alexa. ( different process i know)

Not a major as I have audio in to the camera and we can get a TC slate on everything but I'd still like to know!

Cheers

There are many things that could've gone wrong. Two if those I just mentioned in the post above.
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Constantin , the Amira has TC as well as , sync plugs . Do you need both to jam successfully?

Also , the AC's could not help with the sensor /project issue as they were new to the camera!!!

Vonblake , I'll try the cycle idea .

Cheers

No, just the TC. The sensor/project thing is not specific to the Amira. Strange they wouldn't know about it. It's all in the manual, too.
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So shooting a feature on this camera.

Jamming from my nomad but the camera will slip out of sync by 1 frame roughly after about 4 or 5 takes.

Still trying to figure out the issue.

Also to help out the poor assistant editors if you aren't sending audio to camera make sure you turn off the audio on the camera other wise it will record blank audio tracks and mess up picture sync for separate audio.

Sent from my Nexus 5 using Tapatalk

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And the award for Most Uncalled for Reply 2014 goes to,.,

does the same thing happen if you are shooting something that is not "a feature" ?? By Senator!

---

Also to help out the poor assistant editors if you aren't sending audio to camera make sure you turn off the audio on the camera other wise it will record blank audio tracks and mess up picture sync for separate audio.

This is weird.. Care to elaborate a little? Do the empty audio tracks screw up timecode or is it just that empty tracks are scary for editors?
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CW: " it will record blank audio tracks and mess up picture sync for separate audio. "

and this is based on ..?  :wacko:

 

HUH ??  :blink:

" if you aren't sending audio to camera make sure you turn off the audio on the camera "

off or on, there is no audio (aka blank tracks)... maybe you are charging your clients too much ??

 

" the camera will slip out of sync by 1 frame roughly after about 4 or 5 takes. "

rejam every 3 takes..? sync boxes + external TC ??

Edited by studiomprd
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That timecode issue with it not being able to hold sync for long sounds a lot like the C300; whenever you played a clip back or changed pretty much anything you'd have to re jam the damn thing. Dunno if they fixed that, but it seemed like an issue that could be easily fixed with a firmware update or something. They can't possibly put junk in a camera like that and claim to have that function (except RED of course). In the case of Arri, if they decided to go cheap on the timecode with the Amira then that's just... Well. I can't see how that could have saved a lot of money

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Mike, I mean this in the most respectful way go jump off a bridge, I am too ill at the moment to vet my posts for grammar to your stupid and unhelpful standards. Also jamming ever 3 seconds thank fuck you are here to tell me this, i rented in lockit boxes but god your idea was so much better! I was giving my experiences not asking for help. So if you done being a cunt, shut up.

Olle all I can tell you is that the assistant editor called me, she told me that the audio tracks are switched on and when the camera rolls it is recording blank tracks which is causing her issues on how she syncs. Didn't go to much into detail as I was in bed, battling a bad chest infection on this gig. I will have a proper chat with her about it tomorrow.

Sent from my Nexus 5 using Tapatalk

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Alright Chris!

Mike, I mean that the timecode circuits can't be that shitty in either the V300 or the Amira that it can't be fixed with better software. If they did decide to go cheap on those circuits, then I don't know what it saved them, I mean how expensive are those circuits and clocks? Right now the timecode world is seeing some serious competition with Mozegear and possibly Tentacle bringing prices down. So if they can make that for cheap, then saving on timecode circuits in a camera wouldn't be too much of an economic choice if you look at what the users need/want

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OS: " If they did decide to go cheap on those circuits, then I don't know what it saved them, "

where did you get the idea that they had ??  "decided to go cheap"  ?

That sync didn't hold between takes.

I said that it must be software related, because it wouldn't make sense for them to go cheap on the circuits. And if it's software related then it's just a simple fix (?)

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