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Thanks for that Mark.

Hard to see from the photos if there is anything that needs access on the top.

Nope.

We put boxes there a lot. - I always ask first if there isn't velcro there already, but the universal answer is "on top by the handle."

Side note---

The menu system is very intuitive for selecting sound input and channel assignments. So too, is the TC menu. You'll love it.

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About to do my first Alexa shoot next week.

I'll send an audio scratch wireless via a Sennheiser G2 (getting a 5 pin xlr - 3.5mm made up).

Has anyone had luck finding space to mount a receiver on the Alexa? Is there a cold shoe mount?

Velcro on the side maybe??

Cheers

'Nuther note----

Get a 90* 5 pin and the camera guys will love you. A straight 5 pin connector just gets all kinds of in the way and messes with connecting some of the goodies that camera guys want...

Or as an alternative.. We made one by being handy and cautious with a Dremel tool. Carefully cut a good bit of length from straight 5 pin, make your connections, then fill with epoxy and you will have a wicked strong adapter for very few dollars.

If you like, I'll post a pic in the DIY section.

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About to do my first Alexa shoot next week.

I'll send an audio scratch wireless via a Sennheiser G2 (getting a 5 pin xlr - 3.5mm made up).

Has anyone had luck finding space to mount a receiver on the Alexa? Is there a cold shoe mount?

Velcro on the side maybe??

Cheers

I make these universal Alexa connectors and you can plug anything into it.

post-22-0-15094100-1347034861.jpg

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If the AC doesn't have some widget or cheese-plate thing they want me to mount to the SBT usually goes on with velcro at the place on the dumb side of the camera where it "humps out" rearward of the display. As I mentioned in another thread, we seem to have gone from everyone thinking that the Alexa is fine syncwise on its own, just jam it and let it run on internal sync+TC, to running it with at least EXT TC all the time, if not EXT TC and EXT SYNC, like other cameras. This from the recent batch of ACs and DITs I work with (who include Alexa owners).

phil p

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If the AC doesn't have some widget or cheese-plate thing they want me to mount to the SBT usually goes on with velcro at the place on the dumb side of the camera where it "humps out" rearward of the display.

That does drive me crazy when they don't have a mounting plate. I was sorely tempted to buy one, except that 1) it's not my department, and 2) it's a lot more money than I care to spend. These guys really, really should consider that the cameras have to work in the real world where video monitors, video transmitters, audio receivers, and timecode jam boxes all have to get nailed to the camera. This is a real clusterfu@# when it's a tiny, weird camera like the Canon C300 or EOS-7D.

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'Nuther note----

Get a 90* 5 pin and the camera guys will love you. A straight 5 pin connector just gets all kinds of in the way and messes with connecting some of the goodies that camera guys want...

Or as an alternative.. We made one by being handy and cautious with a Dremel tool. Carefully cut a good bit of length from straight 5 pin, make your connections, then fill with epoxy and you will have a wicked strong adapter for very few dollars.

If you like, I'll post a pic in the DIY section.

Yes please!

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That does drive me crazy when they don't have a mounting plate. I was sorely tempted to buy one, except that 1) it's not my department, and 2) it's a lot more money than I care to spend. These guys really, really should consider that the cameras have to work in the real world where video monitors, video transmitters, audio receivers, and timecode jam boxes all have to get nailed to the camera. This is a real clusterfu@# when it's a tiny, weird camera like the Canon C300 or EOS-7D.

Agreed. Generally, I don't even fuss with mounting. After jamming, I hand the slate and SB-T to the AC and say "here you go." A few minutes later, I'll peek at the monitor to ensure that the TC ic correct, then walk away. I've tried to mount it myself before, and I've found that camera prefers to do it themselves.

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I've tried to mount it myself before, and I've found that camera prefers to do it themselves.

I love it when the AC asks, "and just where would you like me to put this?"

I give him a look and laugh. Usually, I just say, "wherever it works for you, as long as it doesn't stress the cable and it's out of your way. I have extra velcro and straps if you need them."

I also check and make sure timecode is jammed OK (and they know how to jam it), and stay to make sure the camera hop sound level is OK (and they know where those settings are in the menu).

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Richard, do you really have to return the TC setting to INT after jamming it? I left it on EXT for 5 months and jammed without ever changing the menu's with no complaints. Is that specified in the manual?

Just did an Alexa shoot today and couldn't get the camera to read my TC (ambient lock it).

Wouldn't read Ext TC at all.

Any Ideas???

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Alexa user manual here:

http://www.arri.de/c.../downloads.html

Page 102 excerpt:

There are many different ways how Timecode can be used in a production. The 2 most common ways are presented as examples.

External TC, Time of day

• Use: This format is often used on multi-camera productions with sync-sound. The cameras are running on a sync-sound speed, which is also the project frame rate. if done correctly, sound and image time code should match and allow an easy alignment in post.

• Setup: The sound department acts as the Time code master, and generates a Timecode which uses the Time of day as a value, and the time base is the project frame rate. 24 hours of time will translate into 24 hours of Time code.

This Time code is fed to the camera via the LTC in. The camera must be set to Ext LTC Free Run, and the project fps setting must match both the sensor frame rate and the time base of the external TC signal. Then the camera can either use Jam sync mode, in which it samples the TC value once and then continues counting based on its own high-precision crystal clock, and the TC signal can be disconnected from the camera after jamming. This mode ensures stable time code with an offset of less than 1 frame for 8 hours, after which the camera has to be re-jammed. Or the camera can be set to Regenerate mode, where the camera uses the TC value of the external TC signal. This ensures correct CT for an infinite duration, but the TC signal must remain connected to the camera.

• Variations: If the shooting starts close to midnight, the TC might be started with an offset to prevent a rollover at midnight.

• Restrictions: Only possible if the camera is running at sync-sound speed. If the camera is over- or under-cranking, the TC frame rate will no longer match the sensor frame rate, so that TC values would either be duplicate or dropped. Due to this reason, the camera will automatically switch to Int TC Regen, when the sensor frame rate is changed.

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Hmmm....

Still couldn't get Alexa to read EXT TC. Tried everything but no luck. The AC was out of ideas too.

So ended up setting 24hour on the Alexa and jamming on my end.

No further problems, but makes me think camera issue?? Can almost rule out operator error (thanks senator......), but you never know.

Other than that, great camera to work with.

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I am on a set now setup like below everything seems fine. Using a 744t as master. Only thing that bothers me a little is i dont see the i or tc flashing? Is that something fw 6.01 does mot do anymore? Also the tc is lagging about a sec?

Thanks for your feedback

Martijn

Alexa Timecode Jam Sequence 

Date: 2/16/11 

Firmware Version: 3.0RC_12575 

Menu settings for external jam sync: 

            Source:          Ext LTC 

            Mode:            Free Run 

            Generator:        Jam Sync 

            User bit source:  LTC in UB 

Jam Sequence: 

1. Power Camera on, timecode display will begin counting at 00.00.00:00 

2. Plug in sync cable (5 pin Lemo) from jam source 

3. After approximately 2 seconds, "i" will begin flashing on camera display 

4. After approximately 2 more seconds, timecode display will begin flashing and display correct timecode 

5. After approximately 2 more seconds, "i" will stop flashing, timecode will continue flashing 

6. After approximately 2 more seconds, timecode will stop flashing 

 

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I am on a set now setup like below everything seems fine. Using a 744t as master. Only thing that bothers me a little is i dont see the i or tc flashing? Is that something fw 6.01 does mot do anymore? Also the tc is lagging about a sec?

Thanks for your feedback

Martijn

Alexa Timecode Jam Sequence 

Date: 2/16/11 

Firmware Version: 3.0RC_12575 

Menu settings for external jam sync: 

            Source:          Ext LTC 

            Mode:            Free Run 

            Generator:        Jam Sync 

            User bit source:  LTC in UB 

Jam Sequence: 

1. Power Camera on, timecode display will begin counting at 00.00.00:00 

2. Plug in sync cable (5 pin Lemo) from jam source 

3. After approximately 2 seconds, "i" will begin flashing on camera display 

4. After approximately 2 more seconds, timecode display will begin flashing and display correct timecode 

5. After approximately 2 more seconds, "i" will stop flashing, timecode will continue flashing 

6. After approximately 2 more seconds, timecode will stop flashing 

 

The timecode lag of one second is normal, not sure about the flashing 'I' etc.

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Yes, I have seen a 1 second lag on displayed timecode. All they need to do is play back a test shot and see if the camera timecode precisely matches the slate timecode. I may have been lucky, but all the crews I've run into with Alexas have been very hip and have not needed help jamming code. They did need a little help getting camera hop audio into the inputs, but it only took a minute or so.

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Does anyone know how timecode can be extracted from HD-SDI stream and fed as normal LTC to other devices please?

Last time I used an Alexa when it was set to Record Run it did not output that Record Run from the timecode socket.

In the manual P113 it says -

Timecode on external recorders

To guarantee the same Timecode for images that are parallely record internally and exterally, set the external recorder so that it uses the TC embedded in the HD-SDI stream coming from the camera.

or possibly from the EXT cable P119?

Timecode is also transmitted from the master to the slave via the EXT cable. When a camera has been set to slave, it automatically uses the TC values transmitted via the EXT cable. The TC screen will show "EXT TC from master camera" as TC source, and all options are disabled.

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