Raid Arrays

Although not directly connected with any of our existing business Daniel (CB and C2-Cine  IT Support Engineer) and I have been investigating Raid Arrays as a low cost alternative to a SAN for use with video scanning and/or multitrack audio. We tested the external eSATA Raid Arrays on two very different computers.

External Raid Box:

StarTech 3.5in eSATA 4-Bay Raid Enclosure, supplied with its own eSATA interface card.

Throw away the supplied eSATA interface as it has a maximum transfer speed of 60MBytes/Sec. Provided your computer supports SATA then a  eSata cable costs about £6.

Raid Drives:

Four 2TB drives, as our primary interest was in recording and playing back raw video files we selected low power 5400 rpm drives which work better for this application. Sur 

Test Computer 1
AMD Six core 3GHz 1075T, Asus Crosshair III Formula Motherboard, running 64 Bit Windows 7, this machine has 4GB of 1600 Memory and a ATI 4850 video card. The computer supports internal software RAID and has an ESata port

External Raid using 2 x 3.5" 2TB drives in Raid 0 speed approx 180MByte/Sec, There was no advantage in using 3 or 4 drives.

Single 2.5" enclosure with eSATA and USB

USB-2 about 32MByte/Sec

ESata Limited by 2.5" drive speed to about 80MBytes/Sec

Test Computer 2
Toshiba Tecra M10: Two core 2.6GHz Centrino running 32 Bit Windows XP, this machine has 3GB or Memory and is fitted with an ESata Port
Note: XP Maximum partition size is 2TB

External Raid using 2 x 3.5" 2TB drives in Raid 0 speed approx 180MByte/Sec, There was no advantage in using 3 or 4 drives.

Single 2.5" enclosure with eSATA and USB
USB-2 about 32MByte/Sec
ESata Limited by 2.5" drive speed to about 80MBytes/Sec

A few brief conclusions on current setup
1) The processor made little difference to the disc access speed
2) External eSATA Raid drives show no improvement with more than 2 drives
3) If Running XP only then remember the 2TB partition limit
4) Use eSATA not USB-2, I will be checking USB-3 later
5) For hi speed disc access we are looking at internal raid with the drives mounted in caddies
6) If you must use an external raid then use Mini-SAS
7) Our next test will be to compare the built in software motherboard raid with a hardware raid card

FCP/Avid Output to multiple machines

I visited Chris Hellier at Conan on the Warner Brothers lot this week. They needed a software update to work with the Sony PVW2000 machine. Chris uses an RM-6 to make multiple copies from FCP. The FCP makes an auto edit on the RM-6 as a single machine.  The RM-6 controls 5 machines and the same edit is made on each machine, saving a lot of time!

There are a number of settings to make on the RM-6 in order to optimise the performance, There is a data sheet on the RM-6 product page that itemises the changes and provide information on setting up the system.

Future orders that specify the RM-6M will ship with software where these are the default settings.

RM-6 Product Page

SR/RM-6 Interface update - PDW1K6 Blue ray recorder

For faster lock times change
Setup/Root/Iface/Chase/Menu 58 Minimum Slew Speed
Set to 0=

A Curious Case of Record Offsets

Alex Kaiser from ZDF contacted me with an sync problem recently - using a SR-4 and laying back (Recording) audio from ProTools 8.1 to HD VTR's as follows:


Sony A500 Digibeta -In Sync.
Panasonic  AJ-HD1800 - 7 frames late
Sony  HDW2000 - In Sync  .
Sony SRW5500 - 4 frames late


Alex eventually found the reason for the problem - ProTools was setup to use LTC for positional reference
Setup > Session > Positional Reference
This was set to "LTC", when changed to "Serial Timecode" the recording delay disappeared!


Analysis:-

On HD machines there are encode/decode delays. When insert edit is enabled the machines switch to confidence mode (Read after Write). The "LTCout Phase" is set by default to be in sync with playback. On Sony VTR's the menu for this is located as follows

SRW5500:  Menu 618

HDW2000: Menu 617

At ZDF the timecode input of ProTools was connected directly to the video machine.
.
We recommend using the master timecode output of the SR-4/RM-6, this follows the selected master machine. The timecode is regenerated from the master Serial Timecode and is locked to video syncs.


When the same problem occurs with serial timecode it may be corrected on SR-4/RM-6 Software using the Edit Offset Menu
Setup | Root | IFACE | General | Menu 77 Edit Offset
The Edit Offset is added only when tracks on the VTR are armed and only needs to be set once.

New RM-8, SR-4USB Synchronizer

For the last two months I have been working on the new RM-8 and SR-4U, using the latest 32 mips processor (The old processor ran at 3 mips on a good day). The RM-8 has 8x RS-422 ports and the SR-4U has 4x RS-422 ports. The features from the existing software Timecode In/Out, GPIO's, Parallel Remote Control, Macro Keys ( [Again}, [Instant Replay], x10, x8, x6.....) are all included. They both have the following new features

Tri-Level Sync
Combined Bi-Level/Tri-Level video sync input fitted

USB
The USB port is fully functioning and mat be used for direct connection with CBServer or Sony 9 pin Emulation

Ethernet
Fitted for future expansion, we are developing CBServer via Ethernet and remote Ethernet interfaces.

FastStart
A new sync process that compensates for the different machines start-up time by timing the initial play command to each machine.. Originally downstream park was used to implement this but this is not possible with Video or DAW's as they are required to park on the same frame.

The New synchronizers will be released in January next year alongside the current models, it will take a year before the new synchronizers have all the features of the current range.

Bug Report: RM-6 / SR-4 Loss of Comunications

I found a strange communications bug yesterday, all communication stop when the following conditions are met
1) Software fitted with X-Lock ( X-Lock will be displayed in the LCD on power-up or reset)
2) Running timecode connected to the reader
3) Machine reporting a different standard connected to the port

If you think that you encounter this bug
Check the device name displayed in the faulty port, if the standard is different  to the system standard then the standard letter will be added (P(25), N(Non-Drop), F(24), D(Drop). If yes try disconnecting the timecode connected to the reader input,  or Hard Reset (SR-4: [<<] + [Locate], RM-6: [Clear] + [Shift]).

I have fixed this bug on software from October 2010

UR422 as a remote to the RM-6 and CBServer

Jun Yamazaki, The Synchronizer Expert from Japan, asked if it was possible to use the UR-422 as a remote to the RM-6 and CBServer, my reaction "Why Not"

The UR includes dedicated Macro commands to control the RM-6/SR-6 and CBServer Macros that may be programmed directly from CBServer. I asked Jun to work out with his client the layout and functionality that they would like using the existing SR and CBServer Macro's that were available on the UR-422

Using the existing selection of commands he could not meet the clients requirements, after discussing the problem with him I added extra commands and tallies, the final keyboard layout is shown below

The new key macros added are as follows (XMC is the CB multi-machine protocol)

XMC Machine select A..E

XMC Record Enable

XMC Master

XMC Chase Enable

XMC Chase Here

New Menu item

XMC Position Request (Menu Setup), returns position and selected machine

At the same time the Edit In/Out key were improved by adding a menu enabling the user to select from a simple Mark command, Mark, Edit and Set, or Recall, Edit and Set.

If you have special request, please contact me and discuss your requirements.

For the future I am working on UR422config2 that will run on Mac, Windows and Linux – watch out for the alpha test version on “Keep In Sync”