Alexa at 24 fps and Ext TC at 23.98?

[soundtrane]

Hi,

Just wanted to check with the Alexa experts out there.

DP wants to run the camera at 24 fps. Editor wanted me to send 23.98 fps time code to camera.

The Alexa i have here wont do this. i discovered from the manual, the alexa wont accept ext tc at a frame rate different from the project frame rate within the camera.

i read out here that most US work is on 23.98 and if set at 23.98 the alexa blanks out the ext tc option in the time code menu... could it be an older firmware version or something?

-vin

[RPSharman]

Yes. Alexa won't accept different TC.

We use Alexa set to ext TC at 23.98.

Alexa and sound both 23.98, jamming the Alexa from TS3 slates.

Done 3 shows this way without issue.

Maybe if DP wants true 24, you can run your recorder at 24 and 48048 so timeline can be pulled down to 23.98.

But really, they should talk to DP about using 23.98, since it is the norm.

[John Blankenship]

Vin,

While I lay no claim to being an Alexa expert...

The Alexa needs to have its time base and time code both set at 23.98 (23.976) in order to take a jam from a 23.976 source and also in order to enable sound recording. Some ACs, and or DPs, don't realize that time base and time code are two different things, and thus, some of the confusion and issues.

I just ran into this on Monday, with a two Alexa shoot. Both cameras were set to 23.976 time code but wouldn't take a jam or enable audio. It turned out that both had their time base set at 24.

According to a consensus of the most knowledgeable folks here, it seems that, with video cameras, true 24fps is seldom used these days. If it is, then time code and time base should both be at that rate, as well as your audio time code.

I suggest maybe an email outlining the requirements and issues to all parties -- and make sure that all parties know that everyone else has received it -- which may prompt them to get on the same page and avoid an approaching problem. Then, again, politics may dictate otherwise.

Good luck, and let us know how it shakes out.

[studiomprd]

" DP wants to run the camera at 24 fps. Editor wanted me to send 23.98 fps time code to camera. "

they need to talk to each other, workflow test, and you need to get it in writing.

[Marc Wielage]

Note that the Alexa has available frame rates of 23.976, 24, 25, 29.97 and 30 fps. Make sure you know the difference, the crew knows the difference, and you get confirmation from the editor or post supervisor in writing prior to the shoot. [And I just noticed the Senator said the same thing!]

If the camera displays the following error message:

External TC: Incompatible frame rate

Then there's a problem. If the camera will lock to 23.98 timecode, then all is well. My gut feeling is that 24.00fps makes no sense, but there are people who have different opinions.