My home darkroom, now decommissioned, in glorious cylindrical projection. On the left you can see my colour-coded 4x5 development tanks, home-made enlarger timer built from old-fashioned 4000-series CMOS logic chips, and a Beseler 45 MCRX enlarger. The door has vents cut into it to allow airflow, and baffles on the back to form a light trap. The box with the clock attached is built over the window, and contains exhaust fans and light-trap baffles. It has a hatch in it so you can reach through to open the window to allow the fans to suck the fumes out.
Looking into the darkroom from the doorway. In this view you can see the hatch on the fan box.
The front of the door has three rectangular holes cut into it, covered by grilles. The rear of the door, shown here, has a light-trap labyrinth attached to it to let the air through.
The fan box with the hatch open to allow access to the window.