PDA

View Full Version : QUESTION :Tracking


Brötje
08-24-2004, 12:11 PM
Hey,

I'm doing some tracking in Shake. The camera does a pan across the bluescreen and stops as the person in front comes into the frame. Some of the trackmarkers dissapear out of the frame as the camera turns. Can you append the trackers to each other so the track stays correct?

alexx
08-24-2004, 01:57 PM
yes. you can use several tracker markers to track coming and going tracker markers..
but there are some hickups (in 2.46 at least).

- you have to set the in and outpoints of your trackermarkers correctly.
- the second and so on tracker markers have to have the "reference frame" set correctly (that is the first frame the take over the tracking)
- you have to be sure the tangents of your tracker markers are flat for pre and post keys (see that in the curve editor.. after and before the real tracking the dotted curve has to be flat. if not, change the behaviour there)

cheers

alexx

Aneks
08-25-2004, 08:15 AM
Am I mising something ? couldn't you just use the offset tracker region and use the new markers as they come into shot ?

This way you would be getting data from the different points in the same track channel !

What version of shake are you using and also what node are you using ?
stabilise or track ??

alexx
08-25-2004, 09:37 AM
aneks: emm ?
how does that work?
maybe i am doing something way too complicated since years:)

cheers

alexx

Maxim
08-25-2004, 10:14 AM
hi,
check the little crossed box next to the run-forward/run-backward buttons (named "Offset Track from Search Region" in the infobar) before you change your tracking point. then continue tracking.
this should give you a continues tracking path, which is easier to handle like Aneks said.

greetings
maxim

Aneks
08-25-2004, 11:05 AM
Hi Alexx,

sorry if this is something you already know !
I'm talking about tracking when a featureleves fram and there is someting else to tarck to in the same frame. This technique still works if there are gaps in your track but you may have to manually 'fill in the gaps' !

What i'm talking about goes like this:

got to forst frame and place your tracker on the item you wish to track. Trackforeward until this feature leaves frame. Stop your track. Jump back to the last good track frame. Hit the offset track region button, grab the 'X' inside the track region and place it over your next feature. Hit the offset button again and then hit the the track foreward button. This process can be repeated !

here is a pic of the buttons and the resulting offset region thingy!!!

Hope this helps

Aneks
08-25-2004, 11:08 AM
I know I gonna sound like a broken record but I am planning to cover this stuff in an upcomming tut on tracking. Hopefully Paul from vfxtalk will host these when I get them done.

Just too busy at work right now but there are two more tuts almost done:

motion blur in 2d using 3d shaders
tracking

alexx
08-25-2004, 12:48 PM
aneks!

that is something i definitely did not know so far..
i came into shake like not as a compositor, but as a 3d artist who does not have anyone else to make his compositings. thus i was more or less trying myself to get anything sorted out myself. (ok.. i could have looked in the manuals more often :)

so i usually stick to stuff that works for me and dont know about other options. so this one is really new and quite handy i must say. i feel that my method of using several trackers - each one for tracking one feature - is a bit "cleaner".

but thanx for the great tip. i am definitely looking forward to your tutorials - even if i may soud like a broken record on this :)

cheers & thanx

alexx

Ross Forster
08-25-2004, 05:26 PM
Aneks, I'm sure Paul will be more than happy to host anything in the way of tutorial material over at the site.

He'll probably see this anyway. :)

Brötje
08-25-2004, 05:30 PM
Hey Guys,

Thanks for all the help you've given me! I hope there will be some tutorials soon because I really want to go on in compositing.

CHEERS!

ant-
08-25-2004, 06:15 PM
aneks thats a new technique to me too, and i wish i had known it before i did the tracking on my short film, infact i might go back and re do some of the lets just say 'less than perfect tracking' otherwise known as awful tracking


Also can't wait for those tutorials, there is such a shortage of advnaced shake rescources, (and most of what is labeled advanced is more basic than the documentation)

CGTalk Moderation
01-19-2006, 01:00 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.