BenQ HT3550 User Manual - Page 28

INSTALLATION menu Projector Position Auto Keystone The projector can be installed on a ceiling or behind a screen, or with one or more mirrors. See Choosing a location on page 11. Corrects any keystoning of the image automatically. Adjusts the image size and focus and check that the projected image is free from distortion. Test Pattern Aspect Ratio There are several options to set the image's aspect ratio depending on your input signal source. • Auto: Scales an image proportionally to fit the projector's native resolution in its horizontal or vertical width. 15:9 picture • 4:3: Scales an image so that it is displayed in the center of the screen with a 4:3 aspect ratio. 4:3 picture • 16:9: Scales an image so that it is displayed in the center of the screen with a 16:9 aspect ratio. 16:9 picture 12V Trigger High Altitude Mode There are two 12V triggers that work independently according to your needs for installation scenarios. • On: If this is selected, the projector will send electronic signal out when it is turned on. • Off: If this is selected, the projector will not send electronic signal out when it is turned on. We recommend you use the High Altitude Mode when your environment is between 1500 m -3000 m above sea level, and ambient temperature is between 0°C-30°C. Operation under "High Altitude Mode" may cause a higher decibel operating noise level because of increased fan speed necessary to improve overall system cooling and performance. If you use this projector under other extreme conditions excluding the above, it may display auto shut-down symptoms, which is designed to protect your projector from over-heating. In cases like this, you should switch to High Altitude mode to solve these symptoms. However, this is not to state that this projector can operate under any and all harsh or extreme conditions. • Do not use the High Altitude Mode if your altitude is between 0 m and 1500 m and ambient temperature is between 0°C and 35°C. The projector will be over cooled, if you turn the mode on under such a condition. 28 Menu operation