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Richard Hebert
08-17-2015, 09:41 PM
When I use After Effects to track footage, the tracking points are pretty solid. When I import nulls and camera into LW it looks like there is a difference in scaling and the null objects created in Lightwave do not track the background scene properly. I know there is going to be a difference in world scales between packages but does anybody know how to get this to look right using AE? Thanks for all the helpful hints.

Richard

speismonqui
08-18-2015, 10:06 AM
I don't know if this helps but in this video Cody does something to "fix" the scaling (I think), have you tried it?:


https://www.youtube.com/watch?v=O0Bz0RiS5o4&feature=youtu.be&t=414

@7:00min

jeric_synergy
08-18-2015, 10:37 AM
2.... Camera focal length?

Greenlaw
08-18-2015, 12:13 PM
Are you use the native Send Selected Layers to LightWave command? I just ran a quick test with a random aerial cityscape footage I grabbed from Pond5. Even with the low-resolution and giant watermark in the footage, the exported nulls and camera matched up with the footage perfectly in Layout. I used the last 100 frames of this clip: Helicopter Shot of Jaque Cartier Bridge (http://www.pond5.com/stock-footage/20542319/helicopter-shot-jacques-cartier-bridge-montreal-during-winte.html)

If you're using LightWave 2015.3, sending multiple selected items from AE to LW simultaneously should work too.

The scale from AE can be a bit arbitrary because, AFAIK, AE doesn't allow you to be that specific about it. What I usually do is parent the exported AE items including the camera to a null in Layout and scale the parent null up to match the scale I need. Since the camera is parented as well, the tracked motion should remain valid after scaling.

If the AE camera is not lining up in LightWave, check that your frames have been imported to LightWave with the correct settings. You may need to adjust the start frame--if it's off by even one frame, the results can get way out of sync depending on the motion. Also, be sure you're importing whole frames to LightWave and not a movie file. Many compressed video codecs can throw off frame-by-frame playback for animation programs when the codec isn't a 'whole frame' format like, for example, motion jpeg. IMO, it's safer to just use whole frames directly. For LightWave reference footage, I usually like to use regular JPEG at about 60% or less because it allows me to scrub the footage in realtime even across a network. If you're compositing in LightWave and need to use high quality frame footage, just swap it out before rendering.

Hope this helps.

G.

Richard Hebert
08-18-2015, 09:32 PM
OK, it looks like I needed to convert my mp4 footage to an image sequence file. The imported trackers are responding much better at first glance. I'm going to retrack the footage and check out the scaling options as well to get a better understanding of the relationship between apps. Really appreciate all of the input. Kinda lost without the forum!

Richard

Greenlaw
08-18-2015, 10:49 PM
Glad to hear you're getting it to work.

Just to be clear, if you use frames for 3D tracking in AE, you don't want to compress that with JPEG...for 3D tracking (in any tracking program,) you want the cleanest version of footage you can get, uncompressed or lossless (like PNG) if possible. The JPEG suggestion was just for fast playback/scrubbing of reference footage in Lightwave.

G.

Richard Hebert
08-19-2015, 08:43 AM
Got it!