Jun 21, 2010

Direct Video Capture with a Macbook Pro

There have always been situations especially with the newer tapeless cameras, where capturing direct to a hard-disk is preferable to "shooting to cards" and then having to transfer the gigabytes of data over to a hard-drive for storage and subsequent editing.  Here's an example of how to setup a MacBook Pro properly to accomplish the task:

-  15" inch MacBook Pro w/4gb RAM (don't buy RAM from Apple - see my note about RAM later in this post)
-  External FW800 HDD in an enclosure (Seagate 7200rpm 1-TB  drive installed)
-  (1) 15ft 4 to 6 pin FW400 cable w/Ferrite Cores (see note on Cores later in this post)
-  (1) FW400 Repeater
-  (1) 15ft 6 to 6 pin FW400 cable w/Ferrite Cores
-  Sonnet Tech FW800 PCMCIA card
-  Portable power Inverter  (for unlimited power for the Powerbook, external drive and camera on location)

Here' the logic for this setup:

- RAM. I put the maximum RAM in the MacBook Pro so Final Cut or Premiere Pro could run as smoothly as possible in dealing with DVCPRO-HD 720p30.

- External drive: I wanted a decently sized drive to allow all-day shooting or even for the entire project, and migrate between the capture system and the edit system. I also wanted the fastest throughput to avoid any dropouts on the HD content which is why I chose a FW800 drive.

- FW cables & Repeater:  My project has very specific requirements and there will be times when the PB will be quite far from the camera - at least 20 feet at times. Initially I was going to use one 30ft cable to connect camera to PB however, my experience with any FW cable regardless of manufacturer is that beyond 10ft there is significant signal degradation (enough to possibly cause dropouts on capture) and a cable that long can also act an an antenna and pick up tons of RF interference, especially in the studio where monitors, power supplies, etc. will be creating a soup of radio emissions.  So I opted for (2) 15ft footers with a FW400 repeater between them to keep signal strength up and Ferrite Cores on the ends of both cables to help reduce/choke any RF nasties.

- PCMCIA FW800 Card: What's extremely important to note about the PB (and actually the same applies to older G4’s as well) is that both the FW400 & 800 ports live on the same physical bus on the motherboard. Because of the nature of the FW bus, the bus speed is only as fast as the SLOWEST device. The specs on the P2HD data record rate is 100mbps, which means that when connected to a FW port it will choke the entire bus down to FW100 speed! The only way to avoid this is to create a separate physical bus, which the a PCMCIA to FW800 card does. So the camera gets connected to the built-in FW400 port on the MacBook Pro, and the external drive goes into the FW800 port on the PCMCIA card - voila! Two distinct FW800 busses.

- Ferrite Cores: Many pro and pro-sumer video cameras come with a few Ferrite Cores to put on the power supply cable, FW cables and even the XLR cable for the on-camera mic. The reason is simple: All this connectivity is a potential direct path for electronic emissions in the form of radio-frequency interference (RF is the term) to either get in or come out of the camera which could degrade the signal coming out of the camera and into an external capture device, regardless if it's tape or digital media. Ferrite Cores "choke" or in some cases eliminate the RF that travels along the outside of these cables and prevents RF interference from continuing into the camera or your capture device. In point of fact, I've taken this idea and applied it to every cable that is on or around my main edit system for the very same reason - keeping the electronic pathways between devices as "quiet" as possible.

So that takes care of the hardware selection and setup, but there's more that needs to be done in software so the PB can run as efficiently as possible during capture to prevent dropouts. Here's what else do to:

Go into System Preferences and:

- Turn off BlueTooth.
- Turn off the Airport.
- Turn off Screen Saver.
- In Energy Saver: A) NEVER put the system to sleep; B) UN-CHECK "put hard-disks to sleep when possible"; C) UN-CHECK "wake when modem detects ring"; D) UN-CHECK both items for "reduce brightness of display...".
- In Monitors: UN-CHECK "automatically adjust brightness".
- Bluetooth services: UN-CHECK all sharing.
- In Software Update: UN-CHECK "check for updates...".
- Download a the free app "Onyx" and use the "Disable Dashboard" feature (there are widgets that will try to call out to a network connection to update themselves in the background. They are small apps, but I don't want them breathing even a whiff of the RAM for FCP).
- Under Sharing: Don't share anything and turn off the Firewall (if it's on)
- Under Security: Turn off "File Vault" (if you're using it). Using this can potentially cause project corruption in FCP.
- Under Print & Fax: UN-CHECK "receive faxes...". Turn off any printer sharing.
- Under Quicktime: UN-CHECK "check for updates…".
- Make sure your OS environment is clean and stable; run all the cleaning and maintenance routines in Onyx and pick up a copy of DiskWarrior and make sure your directory is in perfect order too.

That's the cleanest, most optimized setup you can get for a MacBook Pro.

Regardless what your hardware setup is, be absolutely sure you follow the software setup listed above so that you don't have things running in the background that can potentially compete for resources during the capture process.

This setup is NOT a run-and-gun setup obviously, nor is it a replacement option for some of the new, direct-to-disk recorders that are on the market but it does give a wealth of possibilities and versatility that don't require using any highly specialized hardware or software and allows you to capture directly from your camera to hard-disk using either "Capture Now" uncontrolled device in Final Cut or Premiere Pro with OnLocation.

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