Hi everyone,

I ran in to a little problem with my dual Kinect Setup. One of the Kinects output is different in scale.
I tested them with the Viewer from Kinect RGBDemo.
I get different Distances for the same point in space. The difference is about 15 centimeters.
AFAIK OpenNI uses the Hardware Calibration directly from Kinect Sensor?
Could it be that one of them is just wrong? is there a way to change it?

Hello!
Could you please share this calibration video with us?

http://www.youtube.com/watch?v=PszvU4VkUMA for how to calibrate 180 degrees.

I deleted the one i took the screenshot from, so i made a new one. It's not as good as the others i did (some lags) but it has the same problem with the scale.
https://rapidshare.com/files/1852935716/video_2011-11-29_10-25-21.rar

Thank you for sharing this video.

It looks like that your problem is "too much yellow". That is too much pixel in which there is no data about depth. As a result ground (floor) plane can't be determined correctly (too little data about floor points). This is the root problem rather than scale.

Tip: try to move your Kinects and/or cover floor with some material (carpet, paper) to minimize amount of yellow on the floor area.

Hi Andrew,

thank you for trying to help me.
I think the yellow points aren't really my problems. I did made a Screenshot from my first calibration tests before i deleted them.

There should be enough points on the ground?

There's another problem with the Kinect on the right Side. This happens sporadically for a few seconds but i can live with that for the moment, the scale issue is more problematic :)

Ok, we'll discover this video in more details.

By the way, problems with right Kinect on your screenshot can concern USB issues. Try to use different USB adapter and make sure that there isn't other device (flash drives, mouse, etc) on the same USB hub.

Hi Scalp,

Is RGB enabled under your preferences?

And your not using one of those after market things on your Kinect Sensor for scale are you?

Hi mrbones,

i didn't know until now that there are "zoom lenses" for the Kinect. So no, i´m using standard Kinects. But they were used by some other guys who did a lot of stuff with openNi. Maybe they changed something in Firmware.
I also have the development Version of the Asus Primesense Sensor, but the iPi recorder doesn't recognize it. Which ist quite understandable :)

The reasons for my USB problems are probably my slow HDD on my Labtop and or as andrew wrote the wireless mouse adapter i´m using. That should be easy for me to fix.

Hi Scalp,

its me Tommy.
Did you fix your problem?

best regards Tommy