I know the air is driest there, but there are radiators below every window, and I am worried it would get too little light if I put it away from the window in a room, not sure though. Sweden is still pretty dark even if we get more and more daylight as the spring will come. I will do some experimenting with the radiator and see if the humidity increases if I lower the heat.
After turning off the radiator the indoor temperature in the room is now 21ºC/70ºF, and the RH is 33-34%. I'm surprised it could make such a big difference, but happy.
I also got a beautiful ("wild") white Phalaenopsis hybrid with small flowers yesterday and grouped a few plants together.
I will look into different desktop humidifiers. Higher RH would be good for us humans too.