title: Relative translation - Aruco
body: <p>I'm using Aruco to find the relative translation between the marker and the camera, I calibrated my camera and got its intrinsic parameters.</p>
  <p>I then have found the relative pose using <code>estimatePoseSingleMarkers</code> function in OpenCV for python.</p>
  <p>My camera is set at a fixed position &amp; height, the only thing changing is the position of the object in the x and y (not in z), by that I mean the object is at a table and not being moved up or down.</p>
  <p>I noticed, however, that when changing the position of the object, all the three values of the <code>tvecs</code> got changed, including the z one, which gets larger as the object move further from the camera.</p>
  <p>I tried to look it up online (how OpenCV estimate the translation?) but with no luck. Could someone please point me out to the way on how the relative position/translation between two frames is done?</p>
  <p>Sorry if this sounds naive question, I'm a newbie to this thing.</p>