Going Tapeless on the Open Seas
Recording direct-to-disk with the Canon XL H1
“We did some tests with DP Scott Billups and settled on the Canon XL H1 for a number of reasons,” says Margouleff. “It’s a tremendous value for the money. The one big thing is the quality of the glass. Canon has been making lenses for so long that that is really what is amazing about this camera.”
To preserve the optimum quality coming out of the camera and to be able to edit immediately on the ship, Margouleff wanted to record direct-to-disk and bypass the MPEG compression. By shooting directly HD SDI out of the camera to a Wafian HR1 disk recorder, Margouleff thought he would be able to shoot in 24p and edit immediately on-set.
Margouleff, however, quickly found that this was not so simple with the XL H1 and turned to Cineform for help.
“If you are transmitting 24p material you typically add pulldown to make it a 60i signal so it is compatible with interlaced monitors,” explains David Taylor, CEO of Cineform. “That’s what Canon is doing out of the XL H1. The have 24p and add pulldown to make it 60i. [To edit in 24p] what you want to do is reverse the pulldown. Normally what you do when you add pulldown is you turn on a flag in the SDI stream that notes the added fields and equipment on the other end recognizes the redundant field and throws it away. Canon didn’t do that. They did not set the pulldown flag. So when we receive 1080i on the other end there is no idea that there has been a pulldown. But we know that the Canon is putting out 24p and it added pulldown so we developed an image processing routine that looks at all the fields coming in and through that it recognizes the redundant fields and throws them out. I have a feeling that when Canon just didn’t think it would be used in this manner. So what we’ve demonstrated is that what was envisioned as a monitoring port is actually a high quality ingest port.”
Another obstacle in the tapeless workflow via the HD SDI line in the Canon XL H1 is that there is no embedded audio or timecode.
To capture the timecode they run a line out of the LTC jack into the Wafian box. Currently the audio is running from the unbalanced outputs of the Canon XL H1 to the Wafian box, but this again posed synch problems.
“Audio data comes down the cable to the Wafian box a lot faster than video,” says Jeff Youle, CEO of Wafian. “So we developed a setting on the HR1 that delays the audio enough so that it will be in synch.”
For recording more than two audio channels, which the audiophile/producer certainly wants, they will have to shoot double system.
“Canon set the camera up basically for high-end ENG use,” comments Margouleff. “But where the camera is going to find a home is in low-end feature production. The audio works fine for 60 and 30, but if your shooting 24p out of the HD SDI you must shoot double system.”
In addition to using the Wafian HR1 as an HD deck, Margouleff also loaded Adobe Premiere and Cineform Prospect HD on the box so they could edit right on the deck of the ship.
“Being able to see a rough cut while we re still on the ship let’s us know if we need to get an extra shot to fill any holes,” says Margouleff. “Plus we can then apply the money that we would have used for the offline towards better shooting, better lighting, more equipment and talent. [Shooting direct-to-disk] makes the medium incredibly flexible and powerful.”
But Margouleff isn’t stopping to push the technical boundaries here and plans on a multi-cam shoot on the ship with many of the cameras controlled remotely from the PC and using an HD SDI switcher to shoot and cut the show live.
“I know it’s a combination of television and cinema but that’s where we are heading,” says Margouleff. “The camera also offers a console whereby we can have all the controls of the camera ‘ the chroma, metering, etc. – on a laptop connected by FireWire so I can put a camera up on a jib or rig it up on the mast. I can set up one camera and then transfer that setup to other cameras so I can have all the cameras matched.”