Yes, our shutters will blackout most of the light, but not all.
You will still get light filtering through the louvre blades and gaps around the hinges. This is perfectly normally you will not be able to block out all of the light just with a shutter.
Everyone has their own ideas of how dark a room should be. As a guide shutters will block out as much light as an average pair of curtains. They are better than wood slat blinds, but not as good as an actual blackout product.