Unexpected scale with motion blur export

Hi, i’m tracking a wall calendar and it tracks nicely.

When i export with CS4 motion blur -setting, the solid i paste the keyframe data to works ok, except it does some really weird scaling at some point.

The layer scale goes from 100 to 600% during half a second, though the solid still tracks perfectly.

the problem is, that when it scales like this, it gets a really bad resolution, and i cant use any footage in it.

i don’t know if you know what i mean, but when exporting with “corner pin data only”, it works - the scale stays the same and the solid still tracks well. but i can’t use motion blur, which really pisses me off.

any clues on this?

thanks,

  • ilmeri

Hi, i’m tracking a wall calendar and it tracks nicely.
When i export with CS4 motion blur -setting, the solid i paste the keyframe data to works ok, except it does some really weird scaling at some point.
The layer scale goes from 100 to 600% during half a second, though the solid still tracks perfectly.
the problem is, that when it scales like this, it gets a really bad resolution, and i cant use any footage in it.
i don’t know if you know what i mean, but when exporting with “corner pin data only”, it works - the scale stays the same and the solid still tracks well. but i can’t use motion blur, which really pisses me off.
any clues on this?
thanks,

  • ilmeri

Thanks for your answer!

But is this related to the motion blur export, as with the option “export corner pin data only” (i’m not sure of the correct phrase, i’m not at mocha atm, but the second option from the dropdown of “export tracking data”) the tracking
works correctly and the scale stays at 100% through the track. It’s only
when exporting with motion blur data i get this error?

.i

Thanks for your answer!
But is this related to the motion blur export, as with the option “export corner pin data only” (i’m not sure of the correct phrase, i’m not at mocha atm, but the second option from the dropdown of “export tracking data”) the tracking
works correctly and the scale stays at 100% through the track. It’s only
when exporting with motion blur data i get this error?
.i

Thanks, i got it now!

Thanks for your answers,

  • ilmeri

Thanks, i got it now!
Thanks for your answers,

  • ilmeri

Hi ilmeri,

The way the motion blur export works is that it puts the basic motion info into the translation, rotation and scale channels, then only puts the remaining motion components into the corner pin channels.

The translation, rotation and scale data is worked out relative to a reference frame, which is the frame where you define your surface in mocha. So if you define your surface in a frame where the object is small, that size will be taken as 100% when you copy to AE. If the object gets bigger, a >100% scale factor will be applied, which results in softening in AE.

To get the best results, you should line up your surface with the object when it’s large in the frame - as close to 100% as possible. This way, most of the scaling will be to <100%, with no loss in quality.

You don't need to align surface in this instance - that's the solution to a slightly different problem. Just make sure you specify the surface in a frame where the object is large.

Hope this helps,

J-P

Hi ilmeri,
The way the motion blur export works is that it puts the basic motion info into the translation, rotation and scale channels, then only puts the remaining motion components into the corner pin channels.
The translation, rotation and scale data is worked out relative to a reference frame, which is the frame where you define your surface in mocha. So if you define your surface in a frame where the object is small, that size will be taken as 100% when you copy to AE. If the object gets bigger, a >100% scale factor will be applied, which results in softening in AE.
To get the best results, you should line up your surface with the object when it’s large in the frame - as close to 100% as possible. This way, most of the scaling will be to <100%, with no loss in quality.
You don’t need to align surface in this instance - that’s the solution to a slightly different problem. Just make sure you specify the surface in a frame where the object is large.
Hope this helps,
J-P

Hi ilmeri,

When an exported track suddenly distorts, scales or twists crazily it usually means the surface in mocha has become too large or rotated past the bounds of the tracking view.

To rectify this, find the largest scale in your scene (where the object/plane you are tracking has scaled up to it’s maximum point) and click the “align surface” button on the left hand panel below the layers. This will pull the corners of the surface to the dimensions of your footage and distort the surface relative to that point.

This means of that you will need to do a little prework in the After Effects composition by corner pinning your intended layer where you desire it at the same frame you aligned the surface in mocha.
You will then need to precompose this layer before you apply the data so your manual corner pin is not touched and the layer is the same dimensions as the comp.

Hi ilmeri,
When an exported track suddenly distorts, scales or twists crazily it usually means the surface in mocha has become too large or rotated past the bounds of the tracking view.
To rectify this, find the largest scale in your scene (where the object/plane you are tracking has scaled up to it’s maximum point) and click the “align surface” button on the left hand panel below the layers. This will pull the corners of the surface to the dimensions of your footage and distort the surface relative to that point.
This means of that you will need to do a little prework in the After Effects composition by corner pinning your intended layer where you desire it at the same frame you aligned the surface in mocha.
You will then need to precompose this layer before you apply the data so your manual corner pin is not touched and the layer is the same dimensions as the comp.