ASK Proxima C40 and C50 (DP2000s and DP2000x) Projectors
Frequently Asked Questions: Installation
Do I have to buy an ASK Proxima ceiling mount? I see that other companies offer mounts for less money. Can't I
just build my own mount?
We strongly suggest that you use an ASK Proxima-approved ceiling mount with your projector. There are two basic reasons
for this.
First, our mounts are designed for a specific projector. They are built so they do not interfere with air circulation in and out of
the projector. This is an important because when you install a projector on the ceiling, you are installing it in the warmest
part of the room. Our mounts are made to bear the weight of the projector. We don't have any 'one-size-fits-all' mounts. We
use heavy-gauge steel and sturdy fasteners.
Second, should anything happen to your projector due to a non-approved ceiling mount, your warranty will not pay for the
repair.
Can I mount the C40/C50 on the ceiling or the wall?
Yes. You use a ceiling mount kit, available from your reseller. You'll probably also want to run installation and video cables to
the projector, as well as a power cable. Many of these items are also available from your reseller. Most people arrange to
have a professional installer mount the projector on the ceiling and run the cables.
You can also mount this model on the wall, as long as it mounted right side up or upside down. The projector cannot be
mounted sideways. ASK Proxima does not sell a wall mount for this projector. Please note that any damage that occurs due
to a non-standard mount is not covered by warranty.
What is the projection ratio (throw ratio) for the C40/C50?
The horizontal throw ratio for the C40/C50 in its default 4:3 aspect ratio is 1.8 - 2.15. There are two ratios because the
projector has a zoom lenses. The two numbers represent the largest and smallest zoom settings.
The horizontal throw ratio is based on the width of the projected image. In the 16:9 aspect ratio, the width of the image
remains the same as in 4:3. Thus, the throw ratio for 4:3 and 16:9 is the same.
How do I use the throw ratio to determine throw distance or image size?
The horizontal throw ratio equals the throw distance divided by the image width. TR = TD / W. Let's say that you want to
figure out how far back to place the C40/C50 to achieve a 100" wide image. For the widest zoom setting, the formula would
be, 1.8 = TD / 100", or TD = 100" x 1.8= 180 inches (15 feet).
For the smallest zoom setting, the formula is 2.35 = TD / 100", or TD = 2.15 x 100 = 215 inches (17.9 feet). In other words,
you need to place the projector 15 to 17.9 feet from the screen to get a 100" wide image.
You can use the same formula to determine what size an image you get when you know what the throw distance is. In this
case, W (image width) = TD (throw distance) / TR (throw ratio). Let's say that you know the projector will be located 12 feet
from the screen. For the widest zoom setting, the formula is W = 144" /1.8 = 80 inches. For the smallest zoom setting, the
formula is W = 144" / 2.15 = 67 inches. Thus, if the C40/C50 is 12 feet (144") from the screen, the resulting image size will
be 67" to 80" wide.
ASK Proxima has created a calculator that automatically provides you with throw distances and image sizes (including
horizontal, diagonal and vertical sizes). It is available from the ASK Proxima website.
Can the C40/C50 be mounted on the wall?
Yes, as long as it mounted right side up. The projector cannot be mounted sideways. ASK Proxima does not sell a wall mount
for this projector. Please note that any damage that occurs due to a non-standard mount is not covered by warranty.
Copyright © 1997-2004 InFocus Corporation.
All Rights Reserved.
Can the image be reversed and flipped?
Yes. You can reverse or flip the image for installation in a rear projection system or on the ceiling. To reverse or flip the
image, press the Menu button on the keypad. Go to Main > Setup > System. Select the Rear checkbox or the Ceiling
checkbox.
How far from the table top or the ceiling is the image cast by the C40/C50? What is the image offset for the
C40/C50?
The C40/C50 image offset is 90%.
What is image offset? The 'image offset' percentage for a projector tells you where the image will appear in relation to the
plane of the lens. An image offset of 0 means that half of the image is above the lens plane and half is below. An image
offset of 100% means that all of the image is above the lens plane when the projector is mounted upside down, with the top
right at the lens plane. An offset value of more than 100% means that the top of image appears a distance below the lens
plane. An image offset of less than 100% means that the top of the image image appears a distance above the lens plane (as
shown below).
4:3 aspect ratio—In 4:3 aspect ratio, the offset value is 90%. This means that the top of the image is above the lens plane
when the projector is mounted on the ceiling (or below the lens plane when placed on a tabletop).
16:9 aspect ratio—At a 16:9 aspect ratio, the bottom of the image is higher than when projected in 4:3 ratio—.125 of the
4:3 image height. This is because a 16:9 image that is the same width as a 4:3 image is also one-eighth smaller on the top
and one-eighth smaller on the bottom.
Calculating image offset—The image offset amount varies, depending on how far away the projector is from the wall and
by how big the image is. To calculate the amount of offset, multiply the image height times .09. (Note: you can find the
image height by using the ASK Proxima Projection Calculator). For a 50" tall image, the top of the image will be the distance
between the ceiling and the lens plane less 4.5".
What kind of screen should I use with the C40/C50? Can I use a light colored wall?
First, for best results, we do not recommend casting images (especially video) on a light colored wall. While you will certainly
get a viewable image, the color reproduction will not be accurate. Wall textures may also create image artifacts.
What screen you use depends on the viewing audience and the amount of light in the room (ambient light). Say the seating
arrangement requires that you have a wide viewing angle and that the room has some ambient light. Choose a screen with a
lower gain (for example, a DaLite HC-Da-Mat, a gray screen with 0.8 gain). If your viewing angle is narrower, you can
choose a higher gain screen (for example the Stewart Grayhawk). Higher gain screens are also better for images larger than
100" wide. One issue to be aware of is that the higher the gain on a screen, the more likely you will notice "hot-spotting" and
sparkles in the image. You should work with your screen supplier to make sure you get the appropriate screen for your
circumstances. Find more information at DaLite Screen Company or Stewart Filmscreen Corporation.
Copyright © 1997-2004 InFocus Corporation.
All Rights Reserved.