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hi,
We’re working on a Feature Film (shot in HDTV 1920x1080_24p) that will need to use a 3D Tracking solution.
We’ll be using Inferno 4.0.3 for visual effects and 3ds max for 3D.
The opening will consist on a actor who will be singing and walking thur different streets in a virtual city.
The actor will be shot on a Greenscreen studio and the virtual city will be created in 3D.
So we’ll need to match the camera movements made while shooting the actor in the Studio with the camera in 3Ds max and with the camera in Inferno.
This opening will have a duration of 2 minutes.
Could anyone give me some recomendations (tips and tricks) on:
– what software would be better for this? Realviz, Boujou, Equalizer or use the Inferno 3D tracker.
– how to mark the greenscreen in the studio. Put marks on the wall, floor and additional objects in the studio that would help the 3d tracking.
Any info. is appreciated since this is the first time we’ll be doing this type of work.
Best Regards.
my suggestion about 3d tracking software would be to use an automatic tracker. both boujou and realviz’s matchmover does this. they both produce good results by automatic tracking and statistical analysis of the track data.
i have had success with importing boujou data into inferno. mind that scaling the setups when exporting from boujou is an issue here, a scale of 100 worked fine for our setup.
matchmover on the other hand also works fine, but it does not at the moment to my knowledge, have an inferno exporter. but you might go through 3dsmax, and import max camera data into inferno.
haven’t used 3d equalizer, but i heard from a colleague that it is not automatic. meaning, you have to measure and do a lot of trial and error.
inferno’s 3d tracker also needs some preliminary measuring and is not automatic like boujou and mm. but since you already have an inferno system, you won’t have to cash extra money.
on expense issue, mm is $5000 and boujou $10000 roughly.
your tracking points should be all around the place. in my experience, the green screen studio is too flat a surface. so additional objects in the studio would be good for the tracker to lock onto.
please be there on the set yourself if you are going to do the compositing. *no one* understands the immediate needs of a special effects shots better than a compositor. if you are not there during the shoot you will have many unforeseen problems.
i hope this helps.
sinan vural
We made a very similar project recently (an actor walking inside a virtual 3d city with camera movement) with Flame and Maya, and we had a lot of problems using Boujou for the 3d tracker. Maybe the reason was that the markers in the croma-real shot were insuficient or bad placed. At the end, the camera movement was similar, but the actor seems to be “floating” in the scene and the camera jitter destroyed all the composite. We found a solution only in half shots, but the shots with zoom or complex pan movement were impossible to made.
For this reason, is very, very important to place enough markers and put it in the right place to reach a good result.Hi Francisco,
I thought you would like some further info direct from 2d3 that would help you plan and decide on the best tracker for your project.
Firstly, exports – boujou exports to 3DSMax as a Max Script file, you need to run the script, load the background sequence and ensure that Render Aperture is set according to the msgbox popup at time of export from boujou.
For Action file exports (as mentioned by sinancg) you may need to change the scale at the time of export, else the cloud point data may appear very close to the camera. boujou exports as *.action so there’s no messing about in other s/w. I recommend you take advantage of exporting only the tracks you need by selecting and ticking “Export Flagged Tracks Only” Inferno doesn’t like 1000 points being imported, this helps to export only the 3D structure of interest. boujou is an extremely popular choice for 2D artists as the 2D tracks are as easy to obtain as 3D solutions.
2 standard mistakes with exports. 1) Starting frame of the sequence is different from the starting animation from the camera track. Always check that the first frames are the same or the track will be ‘out’ by a frame. 2) Check your frame rate is correct in your animation package and in the boujou project file, again symptoms are tracking matching less and less as you play through the sequence.
2d3 recommend triangular markers for blue/green screen jobs (black triangle on white background is fine, though dark and light blue is usually OK depending on the lighting). boujou’s automatic tracker finds corners in an image, so if you put up circles (or crosshairs causing tracks jump between similar looking corners) then the tracker will have problems finding stable features; there are no corners in a circle! The golden rule is – bad features tracks = bad camera path, you are always trying to improve the quantity of quality feature tracks, the best time to ensure you get good results is by getting it right on set. That said boujou does have a shape tracker that can track any contained feature such as a circular marker, it just means more man minutes doing a dull job.
You should try to place the markers at different depths within the scene. Parallax (foreground objects moving faster than background) is the key to getting better results. One step better than this is to block the shot carefully, if you know that there are areas in the shot that will not need keying then leave some studio junk in there or remove the blue screen completely. boujou fires much better on real life objects within a scene. Ladders, Gaff tape, lighting rigs etc are far better for obtaining feature tracks than a single marker is, so if it doesn’t affect the shot then leave it in.
Another trick is to overshoot the sequence. Once the initial action is complete, shoot some more and get the camera moving. You may not be using the end of the shot in the finished edit but it will help boujou get more tracking information about the scene and help nail down a better 3D structure. This is for translating cameras aka Free-Move NOT tripod shots aka Nodal Pan.
See http://www.2d3.com FAQ in the support section for futher info on using the software and setting up your shoot.
As for pricing, boujou is available for hire if your budget is tight – the cost of the rental can go 100% towards a full seat purchase. So there is little risk in trying it out for a one off job, knowing you’re paying for full ownership in the long run.
I still recommend that you put the trackers to a test and try them out. 2d3 have always offered the opportunity for you to get to know the s/w in your own time – no salesperson pointing out which button to press – give it a hammering yourself http://www.2d3.com & click the demo disk link.
PIL – I would like to see the shot that boujou had problems with – we live to see such data.
I hope this is of use – feel free to mail me with any further questions as we have more experience of automatic tracking than anyone else in the world.
Kind regards,
Edwith all the “big boys” already answering, I feel a bit small here, but take a look at http://www.afx.com -the makers of SceneGenie plug-in for 3dsmax which includes a 3d tracker. It’s about one grand!
and http://www.ssontech.com it’s offer a automatic 3d tracker for well under one grand !! Both tracker are feature film proven.-rayk
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