90285f4405b6c94313d4e34f9c57d3731490b667 sets Collada asset ambient light to white, probably to work around https://github.com/ros-visualization/rviz/issues/516. I've just confirmed that this is not an issue, so undoing 90285f4405b6c94313d4e34f9c57d3731490b667 will improve rendering realism.
90285f4405b6c94313d4e34f9c57d3731490b667 sets Collada asset ambient light to white, probably to work around https://github.com/ros-visualization/rviz/issues/516. I've just confirmed that this is not an issue, so undoing 90285f4405b6c94313d4e34f9c57d3731490b667 will improve rendering realism.