ros_camera_info service not found for usb_cam

Hi! I use 2 USB cameras for stereo vision with the usb_cam driver in ROS Groovy and I would like to calibrate them with the camera_calibration package. I start the cameras with the following launch file: they work nicely. Then I want to calibrate them with the following command: rosrun camera_calibration cameracalibrator.py --size 9x7 --square 0.0053 right:=/stereo/right/image_raw left:=/stereo/left/image_raw left_camera:=/stereo/left right_camera:=/stereo/right --approximate=0.005 and it generates the following errors: Waiting for service /stereo/left/set_camera_info ... Service not found Waiting for service /stereo/right/set_camera_info ... Service not found Why? How can I fix it? I know I can use the the `--no-service-check` parameter and it works afterwards, but it won't commit then the calibration parameters to cameras. What is the proper way to do camera calibration with the usb_cam driver? Running the calibration with the `--no-service-check` parameter works and results a `/tmp/calibrationdata.tar.gz` file which contains the `ost.txt` text file with the calibration parameters. But I don't know what to do with this data in order to use the stereo vision. Can anybody help me here? **Update 1:** the /stereo/left/camera_info do exists in my case and the `rostopic echo /stereo/left/camera_info` streams messages like this: --- header: seq: 1383 stamp: secs: 1368623369 nsecs: 14836818 frame_id: left height: 480 width: 640 distortion_model: '' D: [] K: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0] R: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0] P: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0] binning_x: 0 binning_y: 0 roi: x_offset: 0 y_offset: 0 height: 0 width: 0 do_rectify: False --- **Update 2:** the `rosservice list` query results the following output: /rosout/get_loggers /rosout/set_logger_level /stereo/left/get_loggers /stereo/left/image_raw/compressed/set_parameters /stereo/left/image_raw/compressedDepth/set_parameters /stereo/left/image_raw/theora/set_parameters /stereo/left/set_logger_level /stereo/right/get_loggers /stereo/right/image_raw/compressed/set_parameters /stereo/right/image_raw/compressedDepth/set_parameters /stereo/right/image_raw/theora/set_parameters /stereo/right/set_logger_level