Visual Effects Lead: Chris Olivia Director: Robert Rodriguez Production: Terror Planet Client: Troublemaker Studios The double bill feature presentation from rebel filmmakers Robert Rodriguez and Quentin Tarantino, ‘Grindhouse’ offers an authentic peak at the Z-movie exploitation flicks of the 1960s and 1970s. Harking back to a time of grubby little film theatres, smoking in bars, full civil liberties and err...fun, Grindhouse is a celebration of the worst excesses of the genre, which of course makes for some wonderfully unrestrained cinematic entertainment. Though the look of the films is steeped in the past their production involved very contemporary digital visual effects many of which were assisted by The Pixel Farm’s highly acclaimed camera tracking toolset PFTrack. The two features are even punctuated by tongue-in-cheek trailers for other features with names like “Werewolf Women of the SS” and “Machete”, so that the whole presentation resembles a complete cinema package. Previz Animation Each feature bears the signature of it’s director (both of whom acted as their own Director of Photography), so that Tarantino’s “Death Proof” is slower paced, with more emphasis on character development and dialogue, little use of CG and what is becoming his fetishistic trademark of female bare feet. Rodriguez’ “Planet Terror” which was shot on HD Genesis Super 35 Digital Cinematography Camera System (1920x1080), by contrast is jam packed with his trade mark ridiculous, implausible but brilliant action scenes and comic book heroes such as sexy amputee go-go girl, Cherry Darling (Rose McGowan) complete with her snap-on CG M16 machine gun leg. Orginal Plate Such an ingenious prosthetic looks great in the context on screen but was a visual effect that proved very problematic for artists at Troublemaker Digital Studios. Visual FX lead at Troublemaker, Chris Olivia explains, “Her entire right leg needed to be replaced from the thigh down with a CG automatic M16. Being that the gun was much smaller than her leg and that we would have to paint the background that wasn't there, back in, it was vital to get a locked track on both the camera and the leg transform. The camera had a wide angle lens, the dolly in was fast and got extremely close to her leg and it was a pretty dark plate.” Despite all these complications “PFTrack was able to perfectly track the camera, no problem, on the first pass with default settings.” Showing similar enthusiasm for this versatile, easy to use and multi functional tracking and VFX assist package, Chief VFX artist Rodney Brunet adds, “PFTrack was used to solve every camera needed for 3D visual effects in Grindhouse. PFTrack is a great tool and I have come to rely on it. Shot Within PFTrack Apart from the straight forward tracking abilities of PFTrack, it’s object tracking and unrivalled geometry tracking functions also proved invaluable for the team at Troublemaker. From the outset tracking the leg of Cherry Darling which was to be equipped with an M16 encountered real problems. Rod Brunet explains, “Originally we built our tracking pipeline around a particular leg brace which restricted knee bending and was easy to isolate a key." Although this was less than ideal for the actress (Rose McGowan) and ultimately left a shortfall of required data PFTrack was able to extract enough information to be of use. Brunet continues, ”Object tracking worked particularly well on a scene we called ‘the rape scene’, where Wray (Freddy Rodriguez) attaches the machine gun leg on the Cherry (Rose McGowan) for the first time. PFTrack helped capture subtle motion from the performance which became the base layer animation in XSI I'm amazed at the accuracy and how intelligent the software is.” Because object tracking proved so problematic PFTrack’s unique geometry tracking facility came to the rescue providing a solution and a great deal of time. Chris Olivia describes an example of this in a scene where the main character Cherry Darling is on all fours and fires her gun leg (which doubles up as a grenade launcher- obviously) into an oncoming truck. “Because she was pointing her leg almost directly at the camera and at the same time trying to balance herself, there was a lot of movement but not much information to grab onto. On top of that there was some slight bending of the foot and the knee so it was hard to tell where the movement was originating. After trying unsuccessfully to hand track it by eye, I decided to use geometry tracking in PFTrack.” Shot within XSI This allows for the creation of basic geometry within the application itself, which can easily be manipulated and matched to elements within the scene, or alternatively complex geometry can be imported directly into the scene and again perfectly matched to the live action. Olivia continues, “The actress wore a Grey sock / boot over her leg with minimal detail or tracking markers. We were unable to obtain good reference photos during the shoot so we could not build a completely accurate CG representation of the Grey sock /boot. So we just got as close as we could with a rough low rez model. That was brought into PFTrack as an .obj, lined up closely to the boot in the plate, and PFTrack was able to lock the geometry to her leg even as she lifted it and pointed toward the camera. It took only a few hours using PF track. It would have taken me 2 days doing it by hand and it would still not have looked correct. I'm amazed at the accuracy and how intelligent the software is.” The original members of the small in-house creative team working directly for Robert Rodriguez at Troublemaker Digital’s HQ located at an abandoned airstrip in Austin, Texas, include Alex Toader, Chris Olivia and Rodney Brunet. “Robert Rodriguez has the three of us design a look and feel while sorting out technical issues for each of his films” explains Brunet. “This is usually done before a script and studio involvement. Our job is to test and develop a pipeline while hopefully working through issues that may later prove costly to the effects budget” Final Shot This helps explain why PFTrack has become their tool of choice, since it has helped time and again to save both time and money, while providing excellent results for even very difficult shots. Brunet says, “PFTrack helped us place cg props on top of the film plates. Even when the geometry track was less than perfect it gave us a starting point to then hand keyframe the cg element and match the actor’s performance.” Adding, “We do our own on-set supervision to record any and all camera and set information. Many times I used PFTrack to simply generate a point cloud in 3D space to use in set extensions and prop placement.” This multi-purpose must have tracking and VFX assist application from UK developers The Pixel Farm now in version 4.1 features an array of really useful functionality beyond mere tracking which may explain it’s ever growing popularity. Troublemaker Digital Studios have just completed a Martini Commercial starring George Clooney and test trailers for Barbarella and an in-house project called “shorts”. It is also working with an outside Director Nicolas Lopez on his project“Santos”. Visit Trouble Maker at: http://www.troublemakerstudios.com/ Words: Martin Southwood