a different 2 pass motion tracking possible
by Bipop Upreti
on
Jul 17, 2009 at 11:56:03 pm
Hi so i have been getting bad tracks and i know all the usual suggestions "use another track, precomp with curves adjustment, blur out, etc etc. anyways I was thinking of a new idea, and was hoping if someone with knowledge would enlighten me if this would work and if so how to do it.
So, Basically my solution was. if i get a bad track, I would
track the footage to some decency
if track somewhat locks on then stablize the footage.
Precomp it. Now I have a somewhat stablized footage with less movement.
so now i would retrack the footage with the smaller movement which i think AE would track better.
Now my problem is how to reverse 2 tracking data so i actually have camera movements. I know how to reverse track when i have 1 tracking data, but i am confused as to how to do it for 2 seperate datas to get the perfect track.
Re: a different 2 pass motion tracking possible by Peter O'Connell on Jul 18, 2009 at 4:21:30 am
Hi, you can do so with a few expressions between the layer with the tracker data and the layer you want to invert the tracker data for, like so:
anchor point = position
position = anchor point
rotation = rotation*-1
scale = 10000/scale
Re: a different 2 pass motion tracking possible by Bipop Upreti on Jul 18, 2009 at 6:54:21 pm
I would track in mocha but i do not know how to import tracking data for sky replacement, as far as i know mocha exports spatil rotation data and AE doesnt import spatial it imports temporal or vice versa
Re: a different 2 pass motion tracking possible by Ben Heusner on Jul 18, 2009 at 8:33:02 pm
I don't know what problems you've had previously, but you can absolutely bring in rotation data from Mocha. If you want, use a null to contain the tracking data. Ditch the anchor point keyframes and parent your sky layer to the null.
If you can't get a good track of the sky itself, then turn the sky into a 3D layer and push it back in Z-space. Scale it back up to compensate and you should get a good sky replacement.
Re: a different 2 pass motion tracking possible by Jim Dodson on Jul 19, 2009 at 6:45:34 pm
There is a similar strategy that Mackdadd has created called "TrackerViz" -- it is an incredible FREE script that basically allows you to track a layer sveral times (as many times as you want) then AVERAGE all those slightly different tracks together -- the result is incredibly rock steady tracking...
