Try the following troubleshooting steps:
1. Ensure the sensor near the lens is unobstructed.
2. Test Auto Focus in a dim room at a projection distance of 20 cm (7.9 in).
3. Reset the focus mechanism:
- Press and hold the Focus button to enter Manual Focus.
- Move focus fully to one limit (left).
- Then move it fully to the opposite limit (right).
4. Restart the projector.
5. Perform a Factory Reset: All Settings > System > About > Reset > Factory Reset
This will erase all data—back up important files first.
6. If Manual Focus can achieve a sharp image but Auto Focus cannot, perform Focus Calibration.
