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Gangstashers
05-23-2005, 02:40 PM
Hi evryone i renctly got Syntheyser ^^

And i was reading the manual and stuff... ok so i was testing and itsmy first time using a camera tracking program. Anywayz

I used there little demo secne and i needed to export it, so i was searching for cinema 4d? but i could not finde it..

http://img272.echo.cx/img272/9619/check8ni.jpg

Then i saw:

Included exporters for MAXscript (3ds max, 3D
Studio VIZ); Maya scene file; dotXSI - - - - - - ->;Lightwave, Inspire
3D, Maxon C4D, (these three via .LWS);<- - - - - - - - Houdini; Blender;
Hash Animation: Master; Discreet Flame/Inferno(3-D);
Combustion(3-D); Combustion/Flame/Inferno 2-D ASCIItracker
file; After Effects(2- & 3-D); Shake (3.0, 3.5); Nuke;
FLAIR motion control cameras; Electric Image (some
features); and so on

So i exported it as Lightwave. Then i imported it in Cinema 4d R9

Then all i saw was this

http://img272.echo.cx/img272/8008/check25st.jpg

This isnt what it suposed to let me see.. it has to let me see the whole secne including the camera, lighting (Defult though).

Anyone know how to solve this problem?!


Thanks in Advanced.


Sheherryar

rendermania
05-23-2005, 03:23 PM
That is precisely what its supposed to let you see. A few dots representing points tracked and a camera track that you should be able to see when you hit play. To see the original video overlaid as well, you have create a background object in C4D, load the video into a material (with framerate 25 fps for PAL or 29.97 for NTSC) and map that material onto the background object.

If the points don't match the video exactly, this may be due the scale setting in the Lightwave importer. You may be looking at a scene that is scaled too high or too low.

Gangstashers
05-23-2005, 03:41 PM
But i have a friend and if he imports it into Hash Animation Master he can see the video the trackings and the lighting. Isnt there a plugin for cinema 4d export?!

3dg
05-23-2005, 06:03 PM
It does not matter what your friend with Hash sees...what matters is how you do it with the software you have (C4D). As rendermania stated, what you have is correct. All you have to do is create a background object and throw the video (as a material) onto it. Takes a few seconds. Sure, would be nice if syntheyes created a C4D file with everything in place, but I don't see it as much of an obstacle that it does not.

ODoul
05-23-2005, 06:23 PM
OK, my dunce cap is firmly seated on my head. I've heard alot of talk about camera tracking. Even read a few posts about it. I still don't understand what it is ...

Anyone care to enlighten me in 50 words or less ...

fluffouille
05-23-2005, 06:45 PM
Camera tracking allows you to track points on a video file and translate them into 3D space to insert some 3D objects over that video later on.
The 3D camera will match the movements and focal lengh/zoom of the 2D one.

Gangstashers : The lightwave format also allows you to import lights created in Syntheyes in C4D. My advice so far would be to dig into the manual ;)

rendermania
05-23-2005, 07:08 PM
Anyone care to enlighten me in 50 words or less ...

Imagine that I give you a handheld shot where a cameraman was running through an alley, and the whole thing was filmed without a steadycam, so the camera lurches up and down and sideways as he's running.

Now I tell you to animate a running CG character and comp him into that footage - easier said than done.

If the camera were stationary or running on tracks, it wouldn't be a problem to do the composite manually. Here there's a lot of irregular motion on the camera, and the running character's feet need to be pinned to the alley floor.

A camertracking app will extract the (3d) motion of the real camera from the video footage, and transfer it into your 3D app of choice. What you'll get is a scene with CG camera that's keyed to move exactly like the physical camera that did the shot and trackermarkers that denote the position in 3D space of static objects the tracker was able to find in the footage.

Put a running CG character in front of this camera, match the feet up with the floor in the video footage, and it will compe perfectly into the shaky, handheld footage when rendered with an alpha channel. Motionwise at least. The rest is trying to match things like lighting/grain/colorgrading to make the CG match the video backplate as seamlessly as possible.

ODoul
05-23-2005, 07:14 PM
Thank you very much guys. It all makes sense now although I must admit I'm still a bit mystified about how it all works. Seems almost like an impossible task.

rendermania
05-23-2005, 08:37 PM
It looks for pixel patterns in the footage that belong to stationary objects and that it can track across several consecutive frames even if the pattern moves across the frame as the camera lurches. Stuff like the edge of a desk, or the intersection of bricks in a wall, or an antenna mast on a rooftop or similar high contrast patterns. It will look for hundreds of such trackable reference points throughout the sequence. Some it may be able to track for only 10 frames before they get occluded or move outside the camera rectangle. Other points - such as the tip of a far away smokestack - may stay in frame longer.

Because of the parallax effect, tracked objects/points will move differently in relation to the camera depending on their distance to the camera lens. From this difference in movement over time, the software can calculate things like where the camera is in relation to those points and things like its pitch/roll/yaw.

The effect is the exact same as putting motion sensors on a camera and having it record for every frame of footage where it is, what direction its facing and how fast its moving. Except camera tracking software derives this data by working backwards from the footage itself. :)

See if you can get a demo for Boujou or Syntheyes. Its easier to understand how it works if you actually track a short piece of footage (which is very easy and fully automated these days anyway).

rsquires
05-23-2005, 10:22 PM
I am using Syntheyes on a job I am doing at the moment in conjunction with C4d. It is awesome and consistently produces perfect tracks. It has changed the way I approach a lot of stuff. The most compelling thing is that it is amazing value for money at $395. Compared to Boujou, and PFTrack this is just insanely reasonable. Although it has full auto tracking I find myself manually placing about 12 trackers in key points, and this is enough to give me a perfect result. There is a good tutorial on the site about manually feeding the tracker. Have a look at it because it is essential on difficult to track footage, like wild hand held stuff. This is now my preferred method when I want to get the best track possible. Even on stuff that should auto track I find this method to consistently provide the most workable tracks.

See the attached file for the tracking marker set up.
I was working with green screen so I set up a grid of tracking markers using blue ping pong balls on the floor. Why ping pong balls you ask? Because whatever way you look at them they always looks like a dot. I had a few on green poles so I could have mid height markers and also placed blue dots on the back wall. The marker poles were very useful as I was able to move them around easily for different set ups. I used a laser pointer mounted on a tripod to get balls and dots in alignment.

regards

richard

basti
05-24-2005, 08:19 AM
I find myself manually placing about 12 trackers in key points, and this is enough to give me a perfect result.
hi
you're definitely right. never use autotracking because it's just not accurate enough for feature film or even tv productions (btw i remember the syntheyes manual saying this, too - which is quite fair). it's always faster & more accurate to work with manual tracks

if you take a look at the examples at my matchmove homepage (http://www.matchmove.de):
(the cats& dogs face)
http://www.pixellusion.de/public/mm_cat.jpg
these shots are just impossible to track with boujou or any other autotracker

basti :)

fluffouille
05-24-2005, 03:54 PM
Excellent job Basti, did you use Syntheyes for these tracking too? They are to notch.

Great setup Rsquire, what can of things do you usually film in there? People or product shots?

basti
05-24-2005, 04:43 PM
thanks fluffy :)

no, i'm using realviz matchmover. but i guess i'll buy syntheyes, too. it's almost a 1:1 copy of scenegenie for max and i really loved working with sg :)

basti

Sneaker
05-24-2005, 06:33 PM
A good tutorial of the vfx pipeline with Imagemodeller, Cinema4d, Motionbuilder and
Shake can be found in the free tutorials at Pixel Corps (http://www.pixelcorps.com)

-Sneaker

rsquires
05-24-2005, 10:58 PM
Great setup Rsquire, what can of things do you usually film in there? People or product shots?

Hi

it's the first time I have done it really. I basically worked out that rather than grids on the floor what a tracker really craves is dots, and lots of them. I also found out about the balls from doing some research on the web, with regard to placement of markers and best shapes. I work in a tv station so the studio greenscreen was set up. I just placed the markers. The dots are also easier to paint out than lines which tend to degrade how well you can key the edges of your talent.

This shoot was for people/talent for a show opener. I will basically be putting the talent into 3d environments, that although not hyper real, ( no GI etc ) will be bigger and have the show logo incorporated. From the early shots I have completed I am very happy with the result.

regards

richard

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