Is it clean pure black, or some noisy black? Did you check that there is nothing on the lens that would obscure the view (this would likely give you some noisy black)?
If nothing is obstructing the lens, you might have received a defective unit, this would be the 6th bad unit so far out of about 1000 shipped.
Please contact us through kickstarter, you should be able to send a message to the creator. This way, we will get your backer info and we can send you a replacement unit to try out that we will test again before we ship.