Camera lens direction RRS feed

  • Question

  • Hello,

    I have a question about the positioning of the camera lens on Kinect 2. Please look at the following picture.

    Can I ask you if the camera looks perfectly in front of the Kinect (red arrow), or is lightly tilted like the blue arrow? Probably it's a strange question, but I'm encountering some problems, and this could be the reason...

    Thanks and regards

    Tuesday, February 10, 2015 10:41 AM

All replies

  • Someone correct me if I'm wrong but, there will probably be some slight offset, which you can probably find out from the intrinsic camera parameters cx, cy (which you can either measure yourself using any type of camera calibration routine, or find the factory set values that you can see in the coordinate mapping example). If these are exactly 512/2 and 424/2 then the camera is perfectly aligned with the centre of the CCD array. On the Kinects that I've stripped down I have never noticed the CCDs having any kind of offset to the internal heat sink onto which the boards are attached.

    Tuesday, February 10, 2015 12:06 PM
  • Thank you for your answer, Phil.

    Unfortunately I have no experience with camera calibrations; can you explain me how can I check the values 512/2 and 424/2 in coordinate mapping example? Now I've installed and open the project "Coordinate mapping basics -d2d"; where can I find cx and cy parameters?

    Thank you again for your help.


    Tuesday, February 10, 2015 1:19 PM

    This is a discussion on getting the intrinsics out of the coordinate mapper, and hopefully will help out a bit. Just to cover my camera optics, which are shakey at best, the principle point being off centre does not necessarily mean that the camera is pointing somewhere else. The lens may still have its optical axis perpendicular to the image plane, it may just have an offset. But these offsets are controlled for during calibration, either using the factory, or supplying your own. 

    Why do you think you have a problem with the spatial alignments?

    Tuesday, February 10, 2015 1:40 PM