|
|
| Post on "Chasing Ghosts" |
|
|
October 25, 2005
The motion picture community has been transitioning from photochemical finishing to electronic post for the past several years. Electronic scanning, conforming and editing/color correction/visual effects integration—generally referred to as the digital intermediate process—seems out of the budgetary reach of most independent filmmakers. DI budgets for blockbusters are often in the half-million-dollar range, and getting a top-quality DI done for under a quarter million can seem as elusive as the Holy Grail. Many filmmakers, including the producers of the breakthrough indie film Chasing Ghosts, are seeking digital intermediate alternatives in desktop solutions. Chasing Ghosts, scheduled for a theatrical release in September, will be the first film of its kind whose DI workflow was performed entirely on the Apple Power Mac platform. (The digital intermediate process for Dust to Glory, an independent film released in April 2005, was similarly performed on desktop computers, but its producers chose Adobe Premiere Pro and CineForm Prospect HD running on a BOXX HD [pro] workstation.)
Chasing Ghosts is the brainchild of director and editor Kyle Jackson and his producing partner, Alan Pao. It stars Michael Madsen (Kill Bill Vol. 1 and 2) in a crime drama reminiscent of black-and-white noir films such as Double Indemnity. Jackson and Pao wanted to achieve the same sort of tonal quality but with a contemporary look, making Chasing Ghosts a prime candidate for digital intermediate post. DI would offer the film's Wingman Productions the ability to use digital color grading (color correction) instead of traditional color timing at a film lab. The production team researched digital intermediate options around Los Angeles; estimates for a basic DI ran up to $300,000. Fortunately, one small post house, Tunnel Post, accepted the challenge to come up with a DI solution that would be feasible on an indie budget without sacrificing quality.
Desktop Solution for Digital Intermediates
I had a chance to discuss the Mac-oriented desktop approach with Kyle Jackson. "We could have shot Chasing Ghosts in HD and probably avoided a lot of hassles, but in order to get the right look, we opted for Super 35mm negative. The film needed a gritty look, which is helped by the organic nature of film grain, and we wanted the wider aspect ratio of 2.35. Once that decision was made, we researched a workflow that would get us a DI but would remain within our budget. I've been with Apple's Final Cut Pro since before version 1.0—as a beta tester—so that was my logical editing tool. To keep the film-to-tape transfer cost down, we used DV dailies for our offline editing source tapes. Since I was editing on Final Cut, I made extensive use of Cinema Tools to track our film numbers. Chasing Ghosts was edited on my trusty dual-processor G4 equipped with the first version of the AJA Kona card. This setup gave us good looking standard-definition video to watch as I was working through the rough cut."
Once Jackson locked the cut, the fun began. The first step in a typical DI workflow involves scanning a film negative into 2K resolution (2048x1556 pixels) digital files, which requires the editor to generate a negative cut list that the scanning facility can use to find the corresponding selected scenes and takes. There are approximately 1,500 shots in the final approved version of Chasing Ghosts. Jackson worked with Magic Film & Video Works to generate the proper scanning lists (from Cinema Tools) that were then used by Lowry Digital, the scanning facility.
After scanning, the files were delivered on FireWire drives to Tunnel Post, where the raw footage was transferred back to the Mac platform for effects and clean-up work, including dust-busting (digitally "painting out" dirt picked up on the negative). The post team used Apple's Shake compositor for these steps. Next came the crucial stages of assembly and color grading. To allow them to stay on a Mac for the rest of the DI, the Chasing Ghosts producers took advantage of Silicon Color's FinalTouch 2K color-correction system.
This was early on in FinalTouch's development; missing was the ability to match the scanned files—which consisted of numbered image sequences without either Keykode or timecode information—to a timeline of the rough cut. The solution turned out to be a custom piece of software written by Silicon Color engineers that converts a spreadsheet file used to track scanned files into a timeline that can be used by FinalTouch. This software utility has since been incorporated into shipping versions of FinalTouch.
Although this assembly function is a crucial aspect of FinalTouch, the software's real strength is in color grading. Current versions of FinalTouch include workflows for standard-definition video, high-definition video and 2K film and offer a suite of professional primary and secondary color-correction tools. FinalTouch HD sports tight integration with Final Cut Pro's XML lists and direct support for QuickTime media, while FinalTouch 2K allows a colorist to manipulate primaries, secondaries, effects and geometries of both 2K DPX and Cineon files in real time
. Mac-based FinalTouch 2K provides full support for linear and logarithmic color spaces and uses 32-bit-per-channel color processing for visualization and rendering.
Color Grading on the Mac
For the color-grading process, Tunnel Post engineers set up a G5 configured with FinalTouch and the then-newly released AJA Kona 2 card. Most readers will associate Kona 2 with Final Cut Pro as a video capture and output card, but any company that handles image information under Apple's OS X can write drivers and codecs that work in conjunction with Kona 2. Lowry Digital's film scans were delivered in the Cineon 10-bit log data format. (2K Cineon files are 2048x1556 pixels, which amounts to about 12.5MB per frame. Throughput at 24fps is therefore about 300MB per second.)
These files were played by FinalTouch, which was controlling output through the Kona 2 card, so that grading could be monitored on a high-resolution Sony CRT. The Kona 2 card would downsample the Cineon files into uncompressed high-definition video playing at close-to-real-time speed. The playback speed was dependent on drive performance and the number of color-correction filters applied to the clips.
Jackson continues, "We were going for a look that would resonate with modern audiences. We want the audience to be unsure whether our protagonist is a good guy, so we were going for a stylized, edgy look. This isn't a graphic novel on film like Sin City. It's not stark black and white. Instead, we stayed in color, so filming was done with normal contrast. During the grading, we desaturated the colors and pushed the contrast—a little like Sky Captain and the World of Tomorrow, but definitely the real world instead of a synthetic world and without such a painted or glowing appearance. We brought in Teague Cowley as a freelance colorist to drive the FinalTouch system and were quite impressed with the results."
Some will question the accuracy of a CRT in matching a projected image, but Jackson says that, in the end, this wasn't an issue. "We researched using a flat-panel display for correction but didn't like the rendition of the blacks. There aren't enough steps to properly distinguish small differences in dark areas. A CRT, because it is an 8-bit digital display, brings other problems when used to color-correct 10-bit log files from film scans. Peak whites that looked blown out on the CRT monitor, like the exterior light in a window, actually retained some detail on the film print. In effect, the CRT gave us the opposite situation from that of a flat-panel display."
Delivering Your Deliverables
After color grading, Silicon Color FinalTouch rendered the timeline with all adjustments into the DPX file format used in the final film recording stage. Kona 2 was also able to play these DPX files so that final correction could be checked on a video monitor after rendering was complete. A film's deliverables typically include various videotape masters for broadcast and home video distribution. At the time that post on Chasing Ghosts was being wrapped, AJA and Silicon Color were still working on a DPX-to-HD conversion utility, so turning the film files into HD video deliverables was handled through Adobe After Effects. In the future, this process won't necessarily require After Effects.
I questioned Jackson about whether one color grading setting worked for all of their deliverables. "Right now everyone is working out their own solutions. During our research phase, we ran some uncorrected test films through CFI [a Los Angeles-area film lab] and calibrated our monitor to match those results. This way we were reasonably sure that the color grading we were seeing on the monitor would be the same as on the projected prints. In the end, only one reel was a little off and required some minor density correction by the lab. The same corrections held for the TV deliverables, too. Our only video adjustments were to tweak the gamma levels, which was done as part of the file conversion in After Effects."
Did their budget gamble work out? According to Jackson, the portions of the budget earmarked for production and post came to about $1 million, so a DI costing even a quarter of that would have been out of the question. "Even after all the deals you may be able to work, there are always certain hard costs that you can't get away from. For us, the hard cost of scanning and film recording came to around $75,000. In total, counting our costs, freelancers and other items, the complete DI with all deliverables was under $125,000, or less than half of what most studios assume will be the lowest cost for the same process. Using tools like AJA's Kona 2 and Silicon Color's FinalTouch let us work at the highest possible quality and stick with our indie desktop workflow."
Jackson and Pao are so convinced that Chasing Ghosts hit on a winning formula for up-and-coming filmmakers that their Wingman Productions and Tunnel Post have entered into a partnership with Switch Studios in Venice, Calif., to offer the same desktop DI pipeline to other directors. Their new location at Switch Studios provides a facility infrastructure and faster computers, but Jackson isn't about to stray from what he believes are the new indie mainstays: Final Cut Pro HD, Cinema Tools, Kona 2 and FinalTouch 2K.
| COMMENTS (1) | | 11/29/2011 | | The post is written in very a good manner and it entails many useful information for me. I am happy to find your distinguished way of writing the post. Now you make it easy for me to understand and implement the concept. Thank you for the post
<a href="http://www.jihoy.com/">free advertising</a>|<a href="http://www.jihoy.com/classifieds/jobs/5">job listings</a>|<a href="http://www.astrabeds.com/latex-mattresses.html">latex mattresses</a>
|
|
|
|
More...
|
|
|
|
|
|
|
|
|
|