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squarewulf
03-26-2015, 07:30 PM
I have a very stubborn green screen shot with only a few tracking markers on the screen. I've tried AE, and boujou over and over with different settings. Both results were terrible. Does anyone have a good set up for camera tracking manually within LW? I saw this older thread here http://forums.newtek.com/showthread.php?94121-Matchmoving-in-Lightwave But I honestly cant figure out how that works. Any help would be great.

tcoursey
03-27-2015, 08:38 AM
Give Synth eyes a shot.

Greenlaw
03-27-2015, 09:14 AM
Without seeing the footage, it's really hard to say. But I agree with tcoursey...if you have access to SynthEyes, give it a try; I usually have very good luck with SynthEyes. In my experience, every tracker uses different algorithms and techniques, which make some better than others for different situations. If one doesn't work, try another.

You mentioned AfterEffects, so I'm guessing you tried the native 3D camera tracker. Have you tried Mocha Plus? The version of Mocha that comes with AE doesn't export to Lightwave but I think the Mocha 4 Plus plug-in upgrade for AE from Imagineer can send to Lightwave (via AE), and it's $195 is you're an AE CC users. Several friends of mine swear by the full standalone version of Mocha, and I think the Plus version for AE has many of the same features. (It just requires AE to use for certain features.)

My experience with Mocha AE (the version that comes with AE,) has been very good. One time I needed to replace fake cotton snow on the ground and surroundings with images of real snow. Because everything was white and there was almost nothing to track in the footage, plus the camera was handheld and moving all over the place, this seemed like an impossible task to do well. Surprisingly, Mocha AE nailed it almost perfectly. I did all of this completely within AE though and didn't involve exporting data to Lightwave (I did export the rendered frames to Fusion for other details.) Admittedly, I haven't used the Plus version but I think you need this upgrade to export to Lightwave. Hopefully somebody here who has used Plus can confirm or correct any of the info I've written here.

G.

MonroePoteet
03-27-2015, 10:19 AM
I agree with the others: give SynthEyes a shot. The method you refer to in the original post is basically a method of zooming an alternate camera in onto fine details of the background plate (e.g. a pebble, a knot on armor, an arrowhead) and tracking that detail with the alternate camera while keeping the background plate stable with the original camera. SynthEyes has a manual tracker placement, or "supervised tracking" which allows the same method, only built in to the product.

Here's Russ Anderson's tutorial on Supervised Tracking:


Supervised Tracking Master Class (https://www.youtube.com/watch?v=hoL7-aYN-04)

It's an extensive tutorial, but if you skip to 8:30 or so, you see the basic technique being used.

mTp

m.d.
03-27-2015, 12:04 PM
you have to define...it this a nodal pan tripod shot? or a dolly/handheld 3d move
2 completely different algorithms for the solving...

I use both mocha pro, and syntheyes (lately about 4 hours a day for the last 2 weeks)
mocha is really good at tracking crap....i.e. little detail, and fine for nodal pans.... it can do 3d solves...but not in the same league as syntheyes

theoretically you need I think 12 points at least to get a 3d solve...but they should not be all on the same plane.

Tracking markers on the background on a 3d move sometimes will not work out very good as there is so little perspective shift...hence why we put mic stands or such with dots on them around the scene to add perspective for the tracker.

On some greenscreen shots there is only tracking dots on the screen. If there is a lot of perspective shift, it will probably track ok...but if the camera is just moving 1 foot and doing a slow pan, that can really screw up solving... as it is half in between a 3d solve and a nodal pan

If the scene has very bad tracking markers....mocha can lock on pretty well...but it's all manual, and takes a while to solve sometimes

AE tracker can also put out a good solve...but you can't expect to do it automatically....you have to delete bad points attached to actors ect, and on features that are combined by overlapping perspective shifts (edges on walls revealing behind them)
1 bad tracker can make a HUGE difference in both syntheyes and AE...

squarewulf
03-27-2015, 12:11 PM
Thanks for all the replies!

My shot is a free move camera with about 5 tracking markers on a green screen. I've heard of syntheyes but I don't have access to it.

I ended up using the foundrys tracker and it worked well enough for what we needed.