MO-SYS StarTracker Max - Page 68

height of the reference point you are looking at in “Ref H [m]”, in metres. E.g., if the reference
point is on the 󰍔oor enter 0. - Place a crosshair in the real image, e.g., through the camera
view󰍓nder, zoom fully in and pan/tilt the camera to align the reference point in the centre of the
cross hairs, as you would have done in the auto aligner. - The X,Y coordinates of the point, in
metres, that the StarTracker thinks the camera is looking at will be shown in “Ref x [m]” and
“Ref y [m]”. - If this is close to the correct coordinates of the reference point, but the virtual
object is further out, then there is some sort of o󰍒set or lens issue in the virtual set software.
If the coordinates shown are o󰍒 in a similar way to the virtual object, then the issue is in
StarTracker – usually either an o󰍒set or problem in the autoalignment. Verify what is
happening by looking at the object from di󰍒erent positions through the camera to see
where the virtual object seems to be compared to the real reference point. Follow the
sanity check procedures below.
O󰍎sets Checklist
Check there are no unexpected o󰍒sets in the StarTracker in O󰍒sets → Advanced and that
the scaling values are all 1 (or -1) as relevant.
Check that there are no unexpected o󰍒sets in the tracking, map or reference object in the
virtual set software.
Check that you have set the lens limits (zoomed fully in and out, focused fully narrow and
wide), and that the lens encoders 󰍓rmly engage the lens without play.
Check that the coordinates of the points you aligned to in O󰍒sets → AutoAlign → Markers
match the coordinates of the objects you are using to verify alignment.
Check that the Output (studio cam) values in StarTracker match the tracking values in the
virtual set
Follow the through-camera, position sanity and lens checks above to diagnose where the
problem lies.
Real-World Issues
The StarTracker is an optical system so will be subject to local errors and error build-up as
you move away from the origin. These cannot be removed by any o󰍒sets as they are “non-
linear”. However, if the errors are large that is usually a sign of something wrong
If the virtual set design assumes that the 󰍔oor is 󰍔at, but it actually curves or dips in
certain places, even with perfect tracking the graphics may not exactly match the real in
all places as the position of the real 󰍔oor will be o󰍒 relative to the virtual 󰍔oor.
If the StarTracker sensor mount or lens is moved/changed without the knowledge of the
virtual operators (e.g., by maintenance technicians) this can result in o󰍒sets changing for
seemingly unknown reasons. Care needs to be taken when maintaining cameras used for
VR/AR as modifying lenses or moving the sensor bracket has repercussions for the lens
calibration and sensor o󰍒sets, resulting in graphics not matching the real world.
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StarTracker Max Manual
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