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24P timebase workflow for PIX240


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I am trying to find a way to work with true 24P timebase using SD664 as the sound recorder and a PIX240 mounted on a Scarlet-X to record 24P Quicktime proxy files. PIX240 is fed with a scratch track via a Lectrosonics SRb in a Ambient Vslot adapter.
 
I am outputting 1080p24 genlock signal from PIX 240 to a RED Scarlet-X and timecode as well. Video File resolution rate on PIX 240 is set to 1080p24/23.976. Sync Out is set to 24P. Timecode is in Freerun mode. Project time base on the Scarlet is set to 24 and SDI output is set to 24hz.
 
Everything works OK as long as the Scarlet-X powered up and feeds the PIX 240 with a 24hz SDI signal.
 
However, the instant I turn the camera off and SDI output signal on the Scarlet-X disappears, PIX 240 switches to 23.976 timecode. I have verified that this is the case with the monitor function of the jam menu on 664.
 
When I turn the camera back on, the timecode output on the PIX 240 reverts back to 24ND
 
I am curious if there is a way to lock the timecode to 24P mode on the PIX240 even when there is no signal on the SDI input of the PIX240?
 
Here is a video of the timecode generator behavior to illustrate what I mean:

 

pix.MOV

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Ahem, please let me rephrase my question:  If there is no other timecode gear available for the production and a timecode cable between 240 and 664 is out of the question... How would you maintain timecode sync between these three devices while using 24P timebase on all three of them?

 

I've come to the conclusion that the only feasible way to do this is to switch to 23.976 timebase. The final deliverables are a 24 FPS DCP file and a 25 FPS file for broadcast, so the issue will have to be dealt with in the post. It seems to me that working in 24P is just not worth all the trouble as you are likely to run into all sorts of unexpected hiccups like this during the production. Staying in 23.976 all the way to the end and time stretching the audio during mastering is way simpler and more reliable way to do it.

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general notes:

Pix 240 Notes

 

SOFTWARE ver 3.01 is out March 2013. Free on the SD site.      

http://www.sounddevices.com/download/pix-firmware.htm

 

Provides the following new features:

http://www.sounddevices.com/download/pix-firmware/full-detail/

http://www.sounddevices.com/products/pix240i/videos/

Last update provides the following new features and changes.

Fixes

  • Fix: two missing lines when scaling from progressive to interlaced
  • Fix: a rare problem where image could become corrupt with nine images within the same frame
  • Fix: lockup due to rapid re-plugging of the USB keyboard
  • Fix: 1080i50 HD-SDI input interpreted incorrectly as 1080PsF25
  • Fix: no SDI out time code during playback without video input connected
  • Fix: time code hold-off not canceling when time code stops during hold-off period
  • Fix: random rec start/stop with FS700 and time code trigger mode
  • Fix: various other bug fixes and system improvements

Change

  • 3G-SDI output is now full 12-bit
  • SDI input now compatible Sony F55

Interesting notes on ARRI use

http://www.sounddevices.com/notes/general/pix-240i-with-arri-alexa/

 

New Pix 260 rack mount recorder:  http://www.sounddevices.com/products/pix-260.htm   

 

Video Compression space calculator
http://www.digitalrebellion.com/webapps/video_calc.html       Or:

http://www.videospaceonline.com/      And for mobile smart phones

http://www.digitalrebellion.com/webapps/video_calc_mobile.html
Download a calculator for windoze:

It resides on your HD and you don't need an internet connection for it to work:
http://www.aja.com/ajashare/AJA_dataratecalculator_win_11-7.zip
There is also a Mac version, but it is not a separate utility available for download - it’s part of their Mac driver package.  For the iPhone go to the App store and search for AJA DataCalc      it’s a free app. Works nicely. 

 

Sandisk memory CF card from B+H 16G  is $ 80 Sept 2012

http://www.bhphotovideo.com/c/search?Ntt=Sandisk+Extreme+Pro+90+MB%2Fs+%28UDMA+6%29&N=0&InitialSearch=yes

cheaper $ 60: Frys.com  IF THEY HAVE THE 90 SPEED - http://www.frys.com/product/6933177?site=sr:SEARCH:MAIN_RSLT_PG

Buy.com  $ 95.00 -- http://www.buy.com/pr/product.aspx?sku=212751285&sellerid=15334023

 

Best HDSDI cable L-3CFW     see WSV  FAQ on cables (long document)

http://wolfvid.com/datasheets/faq_cat5_cabeling_specs.pdf

 

 

PIX 240    (  this table is clean on my site  check link at bottom)

CAMERA FRAME RATE

SPEED

24 FPS

25 FPS

30 FPS

1/8

192

200

240

1/7

168

175

210

1/6

144

150

180

1/5

120

125

150

1/4

96

100

120

1/3

72

75

90

1/2

48

50

60

1x

24

25

30

2x

12

12.5

15

3x

8

8.3

10

4x

6

6.3

7.5

5x

4.8

5

6

6x

4

4.2

5

7x

3.4

3.6

4.3

8x

3

3.1

3.8

16x

1.5

1.6

1.9

32x

0.75

0.8

0.9

 

Equivalent Shooting Frame Rate 

 

We sell a nice low price bracket for the 240 to make it drop-proof: http://wolfvid.com/datasheets/Bracket_Pix240.pdf

 

The sturdy aluminum handle is powder-coated black and the handles are covered with squishy comfortable bicycle foam. The bracket has a 5/8 inch receiver socket in the rear. You can use your own batteries and connect cables to all PIX 240 original connectors and you will get maximum cable lengths because you are using minimum barrels and extensions.

Size – H 5-1/2” x L 11” x D 3-3/4”.                                  US $ 200.00

           

 

 

 

 We are renting Pix240 in a small bracket with NP-1 batteries good for 10 hours. $ 275/day.

 

Forum for Pix240 only with lots of good info go to

http://forum.sounddevices.com/forumdisplay.php?20-PIX-Video-Recorders

And sign up. It’s easy and there is a lot of knowledge (buried).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This document: Notes on the Pix240 can be found at:

http://wolfvid.com/datasheets/FAQ_Pix240.pdf    

 

PRICES AND SPECS. ARE SUBJECT TO CHANGE WITHOUT NOTICE.   03/01/2013

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Ahem, please let me rephrase my question:  If there is no other timecode gear available for the production and a timecode cable between 240 and 664 is out of the question... How would you maintain timecode sync between these three devices while using 24P timebase on all three of them?

 

I've come to the conclusion that the only feasible way to do this is to switch to 23.976 timebase. The final deliverables are a 24 FPS DCP file and a 25 FPS file for broadcast, so the issue will have to be dealt with in the post. It seems to me that working in 24P is just not worth all the trouble as you are likely to run into all sorts of unexpected hiccups like this during the production. Staying in 23.976 all the way to the end and time stretching the audio during mastering is way simpler and more reliable way to do it.

 

This is an interesting conundrum.  I will have to test whether the code really reverts to 23.976 without SDI signal or if that is just a display bug.

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