@kartia they do have openings on all sides but bare in mind, the more light you let it, the better chance of your subject seeing your movements.
I have added an extra lining on mine to make it less transparent.
Steve, thanks for posting this photo. This is really interesting, I will look for a smaller one (portable) for bird photography, as you can get that much closer. Keep it up!
I have added an extra lining on mine to make it less transparent.