Sometimes when I run the auto tracker to solve a scene, if I switch to the 3D view, my 3D points appear as small white points.  The 3D helpers seem to be absent.  I've tried changing the helper size in the preferences but that doesn't do anything.  And I've tried changing the distance in the coordinate system, but that doesn't do anything either.  Every once in awhile if I create a new coordinate system, it will pop them into place.  But I can't seem to get it to be consistent.  Can someone explain what's happening in these situations?
 
Thanks  in advance,
 
Steve

Humm,
There are several options that can hide 3D points:
Either their hidden attributes is on, or the 3D points are toggled off from the display option of the viewport.
Or 3D helper size can be very small, or they can be reconstructed behind the displayed image plane (you can toggle it by pressing B).
Can you send us your project file so we can see where they are!
Thanks

Sure thing.  The scene file is too large to attach to this post, so I'll have to upload it to my site when I get home this evening.
 
It appears that the size of the 3D helpers is directly tied to the size of the grid.  When I scale my grid up and down, the size of the 3D helpers changes accordingly.  When I've manually tracked a scene, it's fairly easy to create a coordinate system and then adjust the size of the grid.  But with auto-tracked scenes, I'm having trouble getting the coordinate system worked out.  Even after linking it to auto tracks, it still seems that the axis are not correct.  And in many cases, I can't even see the coordinate system from an auto-tracked scene.  I know I can map the world to the camera and that does help realign everything, but I still can't see the grid.  
 
Anyway, that's my latest discovery.  I'll post the actual scene file when I get home.  
 
Thanks again for your help,
 
Steve
 
EDIT:
 
Okay, here's the link to the project file.  I appreciate your willingness to take a look at it.
 
http://www.stevewarner.com/Downloa [...] leaned.zip
 
Cheers,
 
Steve

Hi,
 
Please find below a link to your project "fixed":
ftp://ftp.realviz.com/private/support/Skypan_Niko.zip
 
Your shot is nearly nodal, it doesn't have a lot of parallax, your reconstructed camera path is not correct...
 
The movement is very slow so you don't need so much tracks and keyframes.
 
First of all, clean up your automatic tracked points shorter than 80 or 100 frames.
 
Set the key frame step to 50 ( 3D Tracking tab of the preferences dialog )
 
Select Keyframes and lock them:  
 - "3D Tracking" -> "Select Key Frames"
 - click on the lock icon on the graduation bar in the track view
 
Solve your project (cf niko_solved.mmf)
 
I also tried to add a "nodal pan" constraint even if this shot is not a "real" nodal pan shot.
You can see the result in the file: niko_solved_nodal.mmf
 
Hope it helps,
 
regards,
 
Niko

Niko, thanks for the help and advice and for the time you put into this.  I sincerely appreciate it and it definitely helps.  I hope you don't mind but I have a few more questions:
 
1.  If the 3D helpers don't show up, is that a clear indication that something is wrong with the 3D solve?  I know that the green bar running through the timeline is the best indicator of the quality of the solve.  But are 'missing' 3D helpers also an indicator that there's a problem?  
 
2.  You mention setting the keyframe step to 50.  Is this due to the slow motion of the simulated nodal pan?  I was under the impression that a lower keyframe step value would always be better as it would be more accurate.
 
3.  I noticed that in your project, you didn't have a coordinate system and yet your axis were still basically correct.  When I went through the project again and tweaked it according to your advice, I got similar results.  Is it safe, then, to assume that if your axis are off, that there's a problem with the camera solve?  
 
Thanks again for all your help,
 
Steve