Hasta La Motion!

Why can be locked left mouse button in ‘Linup mode’? So:

Shift+RMB — works OK (z axis).
Shift+MMB — works OK (x/y axis)
Shift+LMB — DON’T WORK (rotation)

Scene is tracked and solved.. Any ideas? :confused:

I’ve been doing a ton of tests every day to improve my ability to track cameras. I can do all the easy stuff like where you keep the same tracking markers in the lens view all the time.

The problem I’m having is just with free move rotations. Let’s say I stand facing down the X axis, take a good 5 steps to my left, and then turn 90 degrees and take another 5 steps so my camera is now facing somewhere around 90 degrees to the right from where it started at the beginning of the shot. This type of camera move makes it so that the things that were in the view at the beginning of the shot are no longer in the shot by the end.. (I will draw a diagram if needed, just let me know how much more info I need to give).

What happens is that I track it, and it comes out good for the most part, but there is some slipping on the test objects. The slipping is strange because the test object slips like it is rotating in the scene, but it is not rotating at all. The test object looks like it’s rotating maybe 15-30 degrees.

I even went as far to put actual tracking markers down on the ground, which one would think that would give me a 100% perfect track because they are at a perfect 90 degree angle and perfect for aligning my scene geometry/grid plane.

My main question is this: Is there some sort of special procedure I need to take on a rotating free move like this? I just can’t seem to get it no matter how many manual markers and how much auto tracking I do. It’s just looks like a perspective issue on the camera, but that shouldn’t be happening because the lens never zoomed.

I also just did a 360 degree turn while stepping forwards and backwards and a little bit side to side, and that turned up bad as well. I need to be able to add rotations to my capabilities.. It can’t be that professional camera tracking people working on the Harry Potter films and such have to tell the technical director and director that the camera movement cannot be a rotation, that would just be silly. There’s gotta be a way to do this!

Thanks for any help!

Today I succeded with my shot.
Atleast as far as I know.

I have posted some questions before in this thread:
http://www.vfxtalk.com/forum/pftrack…tml#post141033

Anyway people requested me to upload pictures for them to help me. Now I have a pretty good track but to learn more I thought Id just ask you guys what type of worklflow you would apply to the specific shoot.

Camera: RED ONE
Lens: Tokina 11 – 16mm
Feature tracks: 10
Autotracks: 575
FPS: 120
Frames: 1600
Size: 2048 x 1024
Type: tiff sequence

It was filmed with a steadicam rig and the operator is running through the scene but since it is 120 fps it is a pretty long shot. In the beginning it is quite blury so that is where most of my problems lye.
The camera enters the room in an arc and then pans through the room focusing on the table.

I started by doing an auto track in the middle where there are loads of good tracking points. The red parts in the images ar approximations of my masks that were used to get rid of bad areas.
After auto tracking I solved the middle are and extended on by more auto tracks. Then I deleted bad points and added my user tracks and improved the solution. Still my solution wasnt good enough so I used the clean features thing and deleted some more points and created 5 different constraints. Then improved the solution again.

The result is a good but not exellent track with a camera error of RMSE 0.416 pixels and Inlier RMSE 0.378 pixels.

Now this is one of the first times I am tracking so I have learned alot but still have loads of questions.

Is this a good error result considering the size of the footage?
Is my workflow good?
If not how would you approach the shot?

My main problem right now though is that the file that I export to maya has ALOT of gliding. Something that isnt apperant at all in PFT.
Do I have to set up maya in a special way?

dew

I have been playing around with pftrack tring to get a good solution for a specific shot.
It has a good amount of motion and camera blur but has quite alot of tracking points so should not be very hard to track.
However I have had quite a big problem with it and it will play in slowmotion so the tracking needs to be perfect.

The shot was filmed with a RED ONE in 120 fps and 2048×1024 resolution.
It starts of with tilt that goes into a pan and ends with another tilt.
During both tilts there is a quite large amount of lens blur and the pan is hard to track in its self.

One question I am uncertain about is the input of focal length and film back.
What numbers are used and why?
I found this link that has some great information:
http://www.jfi.net/RED/REDFormats3.pdf

Following that I use
Frame aspect: 2
Principal point: 49 and 49
Filmback: 11.0592 and 5.5296 (mm)
Pixel aspect: 1
Focal length: Variable

What I am unsertain of is:
Principal point, what is it and is 49×49 correct for me?

Film back: Are those numbers correct?

Focal length:
I am a noob when it comes to photography so bare with me on this one.
If we didnt use the zoom and just used the focus. Does that mean that the focal length is constant?

Specificaly for pftrack what length does it want? Because by looking at the graphical representation to the right in the camera parameters window it seems like it is the total lenght of the lens AND the camera distance to the film back.

Is there anything else that need to be corrected since we only used a part of the sensor or is that included in the numbers from the pdf?

Thanx guys!

dew

http://workaholicstudios.com/trans/kitchen_a.mov