It's not gas that's making it dark, its dust, small particles made out of some combination of iron, silicates, carbonaceous materials, and other elements.
We're near the end of one of the arms of the milky way. There's trillions of stars in between us and the center of the galaxy.
The only real way we'd get an actual image of the center of the milky way is if we somehow maintained connection to a telescope that was billions of light-years away.