Epson Powerlite 7550c Users Guide

							2    Using the Projector             50
The illustration below identifies the parts of your projector.
control panel
status lights
speakersadjustable foot
foot adjust levers
infrared receiver
projector
lens/focus/zoom
hand strap
connectors
rear feet (left   foot not visible) 
						

							Positioning the Projector
51
Positioning the Projector
Your projector supports front, rear, and ceiling projection, allowing 
you to choose the best method for displaying your images. If you 
use rear or ceiling projection, you need to select a special mode in 
the projector’s Setting menu. See page 76 for more information. 
To get the best results, it’s important to position the projector at the 
proper height and distance relative to the screen.
When projecting from a table or desk, place the projector so the lens 
is aligned as closely as possible with the bottom of your screen: 
						

							2    Using the Projector             52
When projecting from the ceiling, align the lens as closely as 
possible with the top of your screen:
Calculating Image Size and Projection Distance
The distance between the projector and the screen determines the 
actual image size. To determine the exact distance required for a 
particular image size (or to determine the size of an image at a 
particular distance), use the formulas given below. (Remember that 
the size of the image can also be changed by rotating the zoom ring; 
see page 54 for more information.) 
						

							Positioning the Projector
53
To determine the minimum and maximum diagonal size of an image 
when you know the projection distance:p
Inches:
Maximum diagonal size = (0.6038 ×
 projection distance) +
 
1.8898
Minimum diagonal size = (0.4631 ×
 projection distance) +
 
1.4000
p
Centimeters:
Maximum diagonal size = (0.6038 ×
 projection distance) +
 
4.8001
Minimum diagonal size = (0.4631 ×
 projection distance) +
 
3.5560
To determine the projection distance when you know the diagonal 
size of the screen image:
p
Inches:
Maximum projection distance = (2.1593 ×
 diagonal size) − 
3.0229
Minimum projection distance = (1.6562 ×
 diagonal size) −
 
3.1291
p
Centimeters:
Maximum projection distance = (2.1593 ×
 diagonal size) −
 
7.6782
Minimum projection distance = (1.6562 ×
 diagonal size) −
 
4.2068 
						

							2    Using the Projector             54
For example, here are the measurements for three installations:* For an image size of 300 inches, the projector may be up to 53.7 feet
 away from the 
screen, depending on the setting of the zoom ring.Image size (diagonal)Horizontal distance from projector to screen
Minimum Maximum
300 inches* (762 cm) 494 inches (12.6 m) 639 inches (16.3 m)
200 inches (508 cm) 328 inches (8.4 m) 423 inches (10.8 m)
100 inches (254 cm) 163 inches (4.2 m) 213 inches (5.4 m) 
						

							Focusing and Positioning the Screen Image
55
Focusing and Positioning the Screen Image   
When an image appears on screen, check that it is in focus and 
correctly positioned on the screen. 
  
p
To focus the image, rotate the focus ring (the front ring on the 
lens). 
p
To adjust the size of the image, rotate the zoom ring (the rear 
ring). Rotate the zoom ring clockwise (facing the projector) to 
make the screen image larger or counterclockwise to make it 
smaller. 
zoom ring
focus ring 
						

							2    Using the Projector             56
If you need to raise or lower the image on the screen, extend or 
retract the foot at the bottom front of the projector as follows:
1. Stand behind the projector and support the front of it while you 
lift the blue foot adjust levers above the adjustable foot. This 
unlocks the foot so it can move up and down. Be careful not to 
drop the projector.
Caution: Don’t hold or lift the projector by its lens. This can 
damage the lens.
2. While lifting the foot adjust levers, raise or lower the projector 
until the screen image is correctly positioned.
rear feet (left   foot not visible)adjustable foot
foot adjust levers 
						

							Focusing and Positioning the Screen Image
57
3. Release the levers to lock the foot in its new position. Make sure 
the foot is locked before letting go of the projector.
4. If the projector is not on a level surface, level the projector by 
turning one of its rear feet to adjust its height.    
Resizing the Projected Image
The Resize button lets you select the projection method for certain 
types of image signals input from a computer. Press the Resize 
button on the control panel or the remote control to select one of the 
following projection methods for your projector.
PowerLite 5550C:p
With images less than SVGA size (800 
× 600 pixels), you can 
either display the image in the center of the projection area or 
display it full size. 
p
With images greater than SVGA size (up to 1024 
× 768 pixels), 
you can project the entire image in a compressed format. If you 
keep pressing the Resize button, the projector will pan around 
areas of the image. The projector automatically reduces the 
image size to the projector’s maximum resolution. 
Note: The Resize button cannot be used with images at SVGA 
resolution.
PowerLite 7550C:
p
With images less than XGA size (1024 
× 768 pixels), you can 
either display the image in the center of the projection area or 
display it full size.  
						

							2    Using the Projector             58
p
With images greater than XGA size, you can either project a 
portion of the image or project the entire image in a compressed 
format. If you keep pressing the Resize button, the projector 
will pan around areas of the image. The projector automatically 
reduces the image size to the projector’s maximum resolution. 
Note: The Resize button cannot be used with images at XGA 
resolution.
Controlling the Projector
You can use the remote control or the control panel on top of the 
projector to do the following: p
Turn the power on or off 
p
Display the help menu
p
Switch between input sources (video or computer)
p
Access the projector menus to adjust video, audio, and basic 
projector settings
p
Resize the projected image (see “Resizing the Projected Image” 
on page 56)
p
Adjust the volume
p
Temporarily display a blank screen and turn off sound 
(AV/Mute button)
p
Freeze the display (remote control only)
p
Display special effects assigned to the Effects buttons (remote 
control only) 
						

							Controlling the Projector
59
Using the Remote Control 
The remote control uses a line-of-sight infrared signal. To use the 
remote control, point it toward the infrared receiver located at the 
front of the projector (see page 50). 
Note: To be able to use the remote control as a wireless mouse, 
make sure you’ve connected the mouse cable to the projector and 
your computer. (See Chapter 1 for instructions.)pointer button
top multi-purpose 
buttonbottom multi-purpose 
button