Optoma EP1690 User Manual page 36

Appendices
Problem: The image is stretched when displaying 16:9 DVD
The projector automatically detects 16:9 DVD and adjusts the aspect
ratio by digitizing to full screen with 4:3 default setting.
If the image is still stretched, you will also need to adjust the aspect
ratio by referring to the following:
Please select 4:3 aspect ratio type on your DVD player if you are

playing a 16:9 DVD.
If you can't select 4:3 aspect ratio type on your DVD player, please

select 4:3 aspect ratio in the on screen menu.
Problem: Image is reversed
Select "Setup  Projection" from the OSD and adjust the projection

direction.
Problem: Lamp burns out or makes a popping sound
When the lamp reaches its end of life, it will burn out and may

make a loud popping sound. If this happens, the projector will not
turn on until the lamp module has been replaced. To replace the
lamp, follow the procedures in the "Replacing the Lamp".
Problem: LED lighting message
Message
Standby State
(Input power cord)
Warming
Normal Mode
Cooling
Error (Lamp failed)
Error (Fan failed)
Error (Over Temp.)
English 36
Power-LED
(Green)
Flashing
Steady light 
http://www.pureglare.com.au
Temp-LED Lamp-LED
Flashing
No light 