Fix apriltag coordinate system notes (#348)

* Fix apriltag coordinate system notes

* Fix apriltag coordinate system notes

---------

Co-authored-by: Mohammad Durrani <46766905+mdurrani808@users.noreply.github.com>

source/docs/apriltag-pipelines/coordinate-systems.rst

@@ -11,24 +11,39 @@ You define the camera to robot transform in the robot coordinate frame.
 Camera Coordinate Frame
 -----------------------
 
-The camera coordinate system is defined as follows, relative to the camera sensor itself, and when looking in the same direction as the sensor points:
+OpenCV by default uses x-left/y-down/z-out for camera transforms. PhotonVision applies a base rotation to this transformation to make robot to tag transforms more in line with the WPILib coordinate system. The x, y, and z axes are also shown in red, green, and blue in the 3D mini-map and targeting overlay in the UI.
 
-* The origin is the center.
-* The x-axis points to the left
-* The y-axis points up.
-* The z-axis points out toward the subject.
+* The origin is the focal point of the camera lens
+* The x-axis points out of the camera
+* The y-axis points to the left
+* The z-axis points upwards
+
+
+.. image:: images/camera-coord.png
+   :scale: 45 %
+   :align: center
+
+|
+
+.. image:: images/multiple-tags.png
+   :scale: 45 %
+   :align: center
+
+|
 
 AprilTag Coordinate Frame
 -------------------------
 
-The AprilTag coordinate system is defined as follows, relative to the center of the AprilTag itself, and when viewing the tag as a robot would:
+The AprilTag coordinate system is defined as follows, relative to the center of the AprilTag itself, and when viewing the tag as a robot would. Again, PhotonVision changes this coordinate system to be more in line with WPILib. This means that a robot facing a tag head-on would see a robot-to-tag transform with a translation only in x, and a rotation of 180 degrees about z. The tag coordinate system is also shown with x/y/z in red/green/blue in the UI target overlay and mini-map.
+
+* The origin is the center of the tag
+* The x-axis is normal to the plane the tag is printed on, pointing outward from the visible side of the tag.
+* The y-axis points to the right
+* The z-axis points upwards
 
-* The origin is the center.
-* The x-axis points to your right
-* The y-axis points upwards.
-* The z-axis is normal to the plane the tag is printed on, pointing outward from the visible side of the tag.
 
 .. image:: images/apriltag-coords.png
+   :scale: 45 %
    :align: center
-   :scale: 50%
-   :alt: AprilTag Coordinate System
+
+|