Galaxies au plafond

Worth saying up front: this shelf is two products sharing a name. A galaxy projector is a lamp. A cinema projector is a screen you point at a wall. Both throw light at a ceiling and that is where the similarity ends, so work out which one you are shopping for before you sort by price. Every product shows its rating and review count from real buyers, which is the only reliable read on brightness.

The night lights run from about $13 to $180. Rotating starry sky and nebula models, an astronaut, a UFO star explorer, a northern lights ceiling projector, a sunset lamp that throws a warm band up a wall, a rotating deer lamp for a child's room, and Bluetooth models that double as a speaker. Judge these on three things. How sharp the star points are, because cheap optics give you fuzzy blobs instead of stars. Whether there is an auto-off timer, which matters if you fall asleep to it. And motor noise, because a hum you can hear in a dark quiet room is a projector you stop switching on.

The cinema half starts around $60 for a small 1080p unit and climbs through 4K smart portables that run Android and cast from a phone, into the high hundreds. There is an inflatable outdoor screen for a garden movie night, a 3D hologram fan, and at the top end a motorized-screen laser TV console that is a piece of furniture as much as a projector.

The honest catch is brightness, and it applies to both halves. Budget projectors are dim in a lit room. Under a few hundred dollars, brightness is the thing you give up, and the picture that looks vivid in the product shot needs a genuinely dark room with the curtains shut. Treat the 4K label carefully too: on cheaper units it often means the projector accepts a 4K signal and displays it at a lower resolution. The galaxy lamps have the same problem in miniature, because a streetlight through a gap in the curtain washes the stars out completely.

So read the reviews from buyers who describe their room, not just their opinion. Sort by rating, check the throw distance against how far your wall actually is, and be realistic about how dark the space gets. Shipping is free and most orders move within a day. Buying for a bedroom ceiling, go to the night light half. Buying for movie night, go to the cinema half and spend more than you first planned on brightness.