RED One Configuration Overview

For using RED One signals with Previzion, there are two things to keep in mind: the sync from the RED preview output is different and the actual preview output is actually at a size of 1280x720px at 59.94Hz. In other words, regardless if you are shooting in 2K, 3K, 4K or 4.5K on the RED One, the preview output is always at a 720p size with a sync pulse of either 59.94Hz or 50.00Hz.

The issue with having the camera output a sync of only 59.94Hz or 50.00Hz is that the Airtrack expects sync at the shooting rate.  This becomes especially problematic when using a frame rate of 23.978 because of the consequent pulldown this creates.  We recommend  two ways of solving this:

• An external sync generator for locking both the Airtrack and the RED One (see RED One Configuration, Sync Generator at 23.98 fps).
• A converter to bring the RED one video to a more standard format and derive Airtrack sync from this signal.

 

RED One Configuration
Sync Generator at 23.98 fps

For utilizing the RED One at 23.98fps, adjust the following:

• In the RED menus, advance the shutter phase by 45 degrees for correct sync. In the RED One menu, this is under “Sensor”, “Shutter Menu” and “Phase”.
• Use the AJA GEN10 (or equivalent sync generator) to generate a 23.98P (NOT 23.98PsF) signal to genlock the RED One and the Airtrack.  Run two separate feed to these and avoid splitting the signal.
• The DIP switch setting on the back panel of the AJA Gen10 for 23.98p is:
  
  
  1. OUT 1-4: HD
  2. OUT 5-6: HD
  3. SD OUT: BLK
  4. FORMAT: 59.94
  5. HD FMT: 1080 or 720 (does not matter)
  6. S1: 0
  7. S2: 1
  8. S3: 0
•  When the DIP switch is set to the above, and the GEN10 is connected to the Airtrack, the Airtrack’s Sync light will switch from red to amber, signifying the presence of a 23.98P (as opposed to PsF) signal. PsF signals generate a green sync light.
• Select the RED sensor size in Previzion (24.4mm — the live preview uses the entire sensor size to provide a “look-around” feature before objects enter the recording frame.)
• When the Sync input in the Tracking tab is set to Airtrack/Intersense, the frame rate displayed on the right hand side of the Previzion UI will display 23.98.
• You may need to erase the old Previzion.ini configuration file for all of the new sensor sizes to show up correctly.
• Select the “1280×720 23.98/59.94i” video input format
• Set the frame delay under the Tracking tab to match the RED One (about 1.5 frames in our tests.)

RED One Configuration
Format Converter at 29.97fps, 25fps

For using RED One signals with Previzion at frame rates other than 23.98, we highly recommend up-converting the signal to a more standard signal that other professional devices understand.  For this, we recommend using a up/down/cross converter box like Decimator Design’s MD-DUCC.

In the RED menus, advance the shutter phase by 45 degrees for correct sync.  This is under “Sensor”, “Shutter Menu” and “Phase”.

The MD-DUCC is a converter box that might as well be the Swiss Army knife of video converters boxes.  It is an inexpensive and effective tool that we strongly recommend.

For 25 fps, 29.97fps, 60i and so on, the procedure is essentially the same: up-convert the signal to 1920x1080px at the closest PsF rate.  Connect the MD-DUCC to the RED One preview output (720p) and, through an active loop, extract Airtrack’s required sync from this retimed scaled output as well as Previzion’s main output.

For setting up a RED One at 29.97:

1. Set your MD-DUCC’s “Scaled Output Format” to 1080/29.97PsF. This will convert the preview output from 720/29.97 @ 59.94Hz to 1080/29.97PsF.
2. Extract Airtrack sync from this signal.
3. In Previzion, select 1920x1080px – 29.97PsF.

For setting up a RED One at 25psf:

1. Set the MD-DUCC’s “Scaled Output Format” to 1080/25PsF. This will convert the preview output from 720/25p @50.00Hz to 1080/25PsF.
2. Extract Airtrack sync from this signal.
3. In Previzion, select 1920x1080px – 25PsF.

The one tricky part of the MD-DUCC is its menu and settings which can be somewhat confusing. For a list of all the menus and settings, download it from:

• MD-DUCC Manual Firmware Version 1.1 Settings

NOTE: VANC (video time code) does not pass through the DUCC, the camera and Previzion will need to pull timecode from an external source. Also the factory setting for the output scaling is OFF. Please ensure that your MD-DUCC’s “Scale Enable” is ON.

RED One Post

The RED One uses a different sensor size for the live output (24.4mm) than for the actual recorded image. For example, shooting standard 4K the full preview uses a 24.4mm sensor width, while the actual image uses a 22.2mm sensor width.

The live preview sensor width is about 10% (1.099x)  wider than the published imaged sensor width for a given window size. (22.2mm* 1.099 ~= 24.4mm.)

The correct sensor size needs to be entered into Maya, Syntheyes, etc. for the data to track properly. (The focal length is a property of the lens alone, and will not change.)

Timecode Sync

The HDSDI preview output of the RED One will sometimes exhibit drift, even when genlocked. This will show up in the Previzion user interface as a red light on the Sync error panel, and an elevated frame rate (26 or 27 instead of 23.9-24.0).

This can be corrected by stopping and restarting the incoming video.

Timecode Embedding

To enable timecode embedding in the output preview HDSDI signal, check the box in the Red menu: Project->Timecode->Output. You can verify the Previzion timecode sync with the Red timecode with Project->Timecode->Display.