Pierre Guilluy wrote:What's the model of your Mac? Are you sure you can't connect a second display on a DisplayPort connector?
iMac (27-inch, Late 2013) Thank you very much Pierre. Sorry for my ignorance. Whats a Display port connector? I just connected the projector with a HDMI cable and are not able to project the output only while Im working at the input.
I understand you're working in mirroring mode, meaning both your iMac screen and the projector are displaying the same content. You can deactivate mirroring and obtain two separate displays by going to Preferences > Displays > Arrangement and uncheck "mirror display". Once that's done you can use your projector for fullscreen while working on the iMac screen.