Different brands of projectors have different methods to adjust brightness. Take the nec 65+ projector as an example to explain it step by step:

1. Connect the projector and turn it on.

2. To adjust the brightness, first press the Menu button on the projector.

3. In the pop-up projection display, right-click to select the "Adjustment" option and press the key to select "Picture".

4. After that, you can adjust the "Contrast" and "Brightness" to make the projection achieve the best effect.