Launch two camera nodes for stereo calibration

Hello, I am attempting to launch two camera nodes via a launch file in order to calibrate them via stereo. Below is my launch file: I am pretty new to ROS and need some help getting this to output two separate image to my monitor, each from separate cameras. Right now I run `roscore` in one terminal followed by `roslaunch (launch_file_name).launch` in another terminal. I get two little grey boxes on my screen but no camera output. I have verified that the cameras are connected as they can be accessed via other software. Any help would be appreciated. Thanks.