Obtaining a preferred projected image size

The distance from the projector lens to the screen, the zoom setting, and the video format each factors in the projected image size.

The native resolution of the projector is 1024 x 768 pixels, which is a 4 to 3 aspect ratio (expressed as 4:3). To be able to project a complete 16:9 (widescreen) aspect ratio image, the projector can resize and scale a widescreen image to the projector's native aspect width. This will result in a proportionally smaller height equivalent to 75% of the projector's native aspect height.

16:9 aspect image scaled to a 4:3 aspect

4:3 aspect image in a 4:3 aspect display area

display area

Thus, a 16:9 aspect image will not utilize 25% of the height of a 4:3 aspect image displayed by this projector. This will be seen as darkened (unlit) bars along the top and bottom (vertical 12.5% height respectively) of the 4:3 projection display area whenever displaying a scaled 16:9 aspect image in the vertical center of the 4:3 projection display area.

When determining the position of your projector, you should consider its intended use and input signal aspect ratios. All inputs (other than composite Video being fed a 16:9 aspect signal) will display in a 4:3 aspect ratio (and will require an additional 33% display height than that of the scaled 16:9 aspect image projection area).

IMPORTANT: Do not select a permanent projector position based upon a 16:9 projection if you will ever need to select an input (other than composite Video being fed a 16:9 aspect signal).

The projector should always be placed horizontally level (like flat on a table), and positioned directly perpendicular (90° right-angle square) to the horizontal center of the screen. This prevents image distortion caused by angled projections (or projecting onto angled surfaces).

The modern digital projector does not project directly forward (like older style reel-to-reel film projectors did). Instead, digital projectors are designed to project at a slightly upward angle above the horizontal plane of the projector. This is so that they can be readily placed on a table and will project forward and upwards onto a screen positioned so that the bottom edge of the screen is above the level of the table (and everyone in the room can see the screen).

If the projector is mounted on a ceiling, it must be mounted upside-down so that it projects at a slightly downward angle.

You can see from the diagram on page 16, that this type of projection causes the bottom edge of the projected image to be vertically offset from the horizontal plane of the projector. When ceiling mounted, this refers to the top edge of the projected image.

If the projector is positioned further away from the screen, the projected image size increases, and the vertical offset also increases proportionately.

When determining the position of the screen and projector, you will need to account for both the projected image size and the vertical offset dimension, which are directly proportional to the projection distance.

BenQ has provided a table of 4:3-aspect-ratio screen sizes to assist you in determining the ideal location for your projector. There are two dimensions to consider, the perpendicular horizontal distance from the center of the screen (projection distance), and the vertical offset height of the projector from the horizontal edge of the screen (offset).

14 Positioning your projector

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BenQ MP721C user manual Obtaining a preferred projected image size

MP721C specifications

The BenQ MP721C is a versatile and reliable multimedia projector designed to meet the needs of various presentation environments, making it an ideal choice for both educational and business settings. With a bright output and an array of features, the MP721C enhances the viewing experience, ensuring that every detail is clear and impactful.

One of the standout features of the BenQ MP721C is its impressive brightness level, measuring at 2400 ANSI lumens. This high lumen output means that the projector can be used effectively in well-lit rooms without sacrificing image quality. The resolution of 1024 x 768 (XGA) allows for crisp and clear images, making it suitable for displaying detailed presentations, videos, and graphics.

The MP721C employs DLP technology, known for its reliability and consistent performance. This technology also contributes to the projector's ability to produce rich colors and deep blacks, enhancing the overall visual experience. Furthermore, the BenQ MP721C includes a built-in speaker that offers decent audio, so users can deliver presentations without the need for external sound systems.

The connectivity options of the MP721C are robust, featuring multiple input ports such as VGA, composite video, and S-Video, ensuring compatibility with a wide range of devices including laptops, cameras, and DVD players. Additionally, the projector includes USB connectivity, allowing users to display images directly from USB drives.

The projector is designed with user convenience in mind. It offers features such as automatic vertical keystone correction, which helps to eliminate image distortion when the projector is not perfectly aligned with the screen. The easy-to-use on-screen menu simplifies the process of adjusting settings, making it accessible for presenters of all technical skill levels.

Moreover, the BenQ MP721C is energy-efficient, with a long lamp life that can reach up to 4000 hours in economic mode, reducing maintenance costs and downtime. Its compact and portable design makes it easy to transport, allowing for quick setup in different locations.

In summary, the BenQ MP721C is an adaptable projector, combining brightness, connectivity, and user-friendly features. Whether in the classroom or a boardroom, it provides an effective solution for making presentations stand out, while ensuring reliability and longevity for regular use.