Christie Digital Systems Ds+4k, 8k, Dlv1400-dx, Mirage S+2k, 4k, 8k Users Manual

							Section 3: Operation 
 
  
 User’s Manual     3-49. 
Typically, a high-end graphics workstation that includes hardware and software tools 
for customizing video output timing parameters can produce the requisite 3D signals, 
as can a PC running Windows
TM 98/2000 (use the “PowerStrip” utility)—
consequently your 3D displays should originate from either of these sources, or one 
that is similar.  NOTE: Not all systems include the hardware/software necessary for 
reconfiguring the 3D video output timing parameters—these sources may not be 
compatible with Mirage. 
In addition, Mirage requires the following conditions for 3D work at these higher 
frame rates: 
3D Source Requirements and Conditions 
•   Use a progressive RGB source with native resolution up to 1400 x 1050 (can be 
cropped if desired). Higher resolution can be used, but edge pixels will be 
cropped rather than the image resized to fit. 
•   92-115 Hz input frame rate if SXGA+ resolution. 
•   Pixel rate must be less than 220 MHz 
•   Requires at least 14 lines of vertical blanking 
•   Use minimized line rates (horizontal frequency) 
•    3D produces only a single frame of delay, limits some resizing (particularly 
vertical) and position ranges.  
Typical hardware configurations for active and passive 3D systems are shown in 
Figure 3.25, Figure 3.26, Figure 3.27 and Figure 3.28. Hardware descriptions follow 
the illustrations. 
 
Figure 3.25. Typical 3D Configuration with Active Glasses & TTL Inverter 
 Hardware Requirements  
						

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Figure 3.26.  Typical 3D Configuration with Passive Glasses & TTL Inverter 
 
Figure 3.27. Typical 3D Configuration: Active Glasses & 3D Stereo Sync Cable  
						

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Figure 3.28. Typical 3D Configuration: Passive Glasses & 3D Stereo Sync Cable 
• APPROPRIATE 3D SOURCE: Signals from your 3D source (workstation or PC) 
must be customized to precisely match the processing capabilities of the 
projector. In addition, the source must provide a separate synchronization 
signal that precisely controls when left/right fields are visible through the 
viewer’s glasses. 
• 
INVERTER: Your 3D displays will usually require adjustment of frame delay, 
which can be approximately 1-3 frames set in 1-line increments. If the delay is 
1 frame or 3 frames it needs correction (i.e., reversal of frames), otherwise 
image data intended for one eye would be delayed and seen by the other—
images would lose their 3D quality. If a 3D (stereographic) source cannot 
invert the signal, thereby synchronizing the left/right shutters in your 3D 
glasses with the corresponding images displayed by the projector, you can 
invert via a left/right TTL inverter or by using the 3D Stereo Sync Cable and 
the proper 3D Stereo Sync setting in the Advanced Image Settings menu. Either 
configuration ensures that shutter changes in the glasses allow each eye to 
receive the image data intended for it, regaining the 3D effect in the display. In 
addition, you can lock the R/L signal to Mirage’s output frame sync. 
NOTE: Depending on your workstation, you may be able to reverse left/right 
frames through software only, eliminating the need for separate inverter 
hardware or the 3D Stereo Sync Cable. 
• 
IR EMITTER: In response to an incoming sync signal, this small device emits 
left/right IR signals to a receiver in active 3D glasses, causing their left/right 
shutters to alternately open and close for active 3D (stereographic) 
applications. Connecting one of the 3D Stereo Sync Cable outputs to an emitter 
also enables you to switch back-and-forth between active and passive systems, 
if desired. 
• 
GLASSES: Active glasses differ in speed/performance—consult the documentation 
for your glasses and keep their specifications in mind when reconfiguring your 
source signal. The input signal must be optimized for the available shutter 
speed in order to prevent obvious “ghosting” of image content (known as  
						

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cross-talk in 3D (stereographic) applications) as well as other more subtle color 
artifacts. Such problems indicate that the eyes are detecting portions of the 
opposing frame due to an “out-of-sync” system, and can occur in either active 
or passive 3D configurations. 
In the Advanced Image Settings menu, the correct “3D Stereo Sync Delay” 
setting helps to synchronize glasses with the displayed images. See also 
Customizing the Input Signal, below, for examples of well-synchronized 
systems. 
NOTE: In a passive system, where glasses do not have shutters and instead 
depend on the speed and accuracy of the Pi Cell polarizer, the input signal 
must be synchronized with the polarizer. 
 
To customize your 3D (stereographic) input signal for use with the projector, you will 
need access to software that controls video output timing from the graphics source.  
The display must be synchronized with shutter control—called gating—so that each 
eye receives only the frames of data intended for it, otherwise you will detect 
opposing data frames (cross-talk) and see faulty images. This requirement means that 
timing parameters in your source should guarantee the following: 
◊ Each new frame begins after the opposing shutter mechanism is closed  
◊ Each frame completes its display before the opposing shutter mechanism 
begins to open. 
◊ Each frame (mirror sequence) is displayed in its entirety to the correct eye. 
What To Adjust 
Since most current 3D-video sources (stereographic) do not have the necessary 
characteristics for use with Mirage, you must synchronize the projector’s display with 
your gating mechanism by adjusting the vertical sync width and/or vertical back porch 
of the input signal and, in many cases, by adjusting the projector’s “Dark Interval” 
control. These two parameters—input timing and dark interval—are described below. 
Note that because they interact with each other, you may have to go back and forth 
between them when optimizing the 3D display. 
(1) Vertical sync width and/or vertical back porch blanking of your input source. 
Choose the vertical sync width and/or vertical back porch timing to determine 
when the next field begins displaying relative to the vertical sync signal. The 
degree of timing adjustment needed depends on the specific signal at hand as 
well as the performance of your glasses. An example of improvements to poor 
synchronization is shown in Figure 3.29. After adjustment, shutter changes 
occur during the dark interval between frames. 
NOTE: The example in Figure 3.29 assumes that the first active line of your signal is 
displayed on the first line of the Mirage display panel rather than being repositioned 
higher or lower using the projector’s V-Position control.   Software Re
quirements 
 Customizing the 
 Input Signal  
						

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Figure 3.29. Customizing the Input Signal  
						

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Figure 3.30. Examples of Poor and Ideal Synchronization 
(2) DARK INTERVAL — (note: not always required). For slower gating 
technologies, you may also need to artificially increase the amount of dark 
time between displayed frames so that shutters have even more time to 
open/close and each eye sees the full display intended for it (Figure 3.30B). 
Symptoms are more subtle than cross-talk—if the dark interval is too brief for 
proper gating, you may notice an apparent color temperature problem, with 
some whites or grays appearing with a slight red, green or blue tint. This color 
artifact is particularly easy to diagnose in a grayscale test pattern displayed in 
3D (stereographic) mode. In the Advanced Image Settings menu, increase the 
“Dark Interval” as necessary until the grayscale is correct—you may also have 
to increase the internal frame delay when using a longer Dark Interval. The 
Dark Interval range of adjustment depends on the vertical frequency of your 
source—the higher the frequency, the smaller the range.  
						

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NOTES: 1) Increasing the Dark Interval decreases the peak brightness of the 
image. Use only if necessary—you may prefer some color artifacts rather 
than reduced brightness, or vice versa. 2) Higher input frame rates limit the 
range of Dark Interval adjustment. 3) Faster glasses allow a briefer dark 
interval. 
(3) 
3D STEREO SYNC — This option defines 1) whether or not the incoming 3D 
(stereographic) signal locks to the vertical sync output so that signals are 
synchronized, and 2) whether or not the frames must be inverted, i.e. swapped 
left-with-right. The correct setting ensures that the projector’s 3D display of 
left/right frames is synchronized with other 3D system components so that 
left/right image data is seen by the intended eye. Select the option 
corresponding to your 3D source connections and timing, and use only if the 
Mirage 3D Stereo Sync Cable is connected between the projector’s GPIO port 
and a server (this cable replaces the need for a separate TTL inverter as 
described in 3.9, 3D Images). Keep this adjustment OFF (default) when you 
are not using the 3D Stereo Sync Cable. 
 
With your sync cable, Z-screen and, if desired, emitter connected as described 
in 3.9, 3D Images, select the option suited to your 3D configuration (see 
above). If frame delay is 2 or 0, do not invert; if frame delay is 1 or 3, invert. 
Generally, an “Unlocked” setting is synchronized with the incoming L/R signal 
rather than the vertical sync output, and may be needed only with multi-
projector installations in which the vertical sync outputs vary slightly. 
(4) 
3D STEREO SYNC SELECT — Define which of the Mirage 3D Stereo Sync 
Cable’s input connecters is routed to your server. Input A = BNC connector, 
Input B = 3-pin mini-DIN connector. Use only if the cable is present. 
 
(5) 
3D STEREO SYNC DELAY — Set when the L/R frames begin, defining the best 
reference point for synchronizing the display with your glasses. Proper 
adjustment should eliminate cross-talk and odd colors caused by timing 
differences between the glasses and the projected display. Use this slidebar 
only if the Mirage 3D Stereo Sync Cable is connected between the projector’s 
GPIO port and a server. Slidebar values indicate the number of lines that are 
delayed. 
 
The following illustration shows the various relationships between signals and Mirage 
software adjustments for 3D images.  
						

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When using a 3D Stereo Sync cable at the Mirage GPIO port, select which 3D Stereo 
Sync input (A or B) is connected, adjust the 3D delay, and choose the 3D Stereo Sync 
locking/inversion options applicable for your installation. See below. 
The following sources are optimized for active 3D (stereographic) images using the 
projector and active glasses. Clamp Location is “Back Porch”. Keep in mind that 
formats beyond those shown below may also be compatible. 
Table 3.4. Compatible 3D Sources 
   Horizontal Timing Parameters (Pixels) Vertical Timing Parameters (Lines) 
Glasses Speed Vert. Rate Pixel Rate Front Porch Sync Width Back Porch Front Porch Sync Width Back Porch 
closed 
						

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IMAGE IS BREAKING UP: The horizontal back porch may be too small or too large. If 
you can lock to the signal by changing H-Position but have a black left edge in the 
image, reduce the source’s horizontal back porch blanking. If the black edge is on the 
right, increase the source’s horizontal back porch blanking. 
HORIZONTAL STREAKS IN THE IMAGE: You may need to adjust the Clamp Location 
option in the Input Levels menu (accessed via Image Settings menu) with 4- or 5-wire 
signals. 
COLORS ARE “OFF”: If some grays in your grayscale appears tinted when viewed in 
3D, your glasses may be slightly slow for the current signal setup. 1) If possible, 
adjust the projector’s Dark Interval control. 2) Double-check timing adjustments to 
the source. 3) Use faster glasses. 
 
When an installation requires multiple projectors, you can use the RS232 serial ports 
to daisy-chain the units together and control the group with a single keypad or a 
computer/controller connected to the first projector. In such a network, you can 
choose to broadcast commands to the entire group, or use the 
Proj key as desired to 
limit responses to an individual projector. 
Alternatively, you may want to add projectors to a hub on an Ethernet network. 
NOTE: Refer back to 3.6, Adjusting System Parameters and Advanced Controls for 
complete information about communicating with multiple projectors. 
In a multiple-projector wall, you will likely want to precisely match color and intensity 
from image-to-image so that the full wall is as uniform as possible. This matching is 
typically done in conjunction with Brightness Uniformity and Edge Blending. 
Preliminary Calibration 
As a final part of the manufacturing process, all primary colors in the projector are 
precisely set to pre-established values to ensure that overall color performance is 
optimized and is as accurate as possible (refer back to Figure 3.19). Upon installation 
at a site, however, lighting and other environmental factors may slightly change how 
these colors appear on your screen. While the change is negligible in most cases, you 
may prefer to recover the originally intended color performance before trying to 
match colors from several projectors. Or you may be renting a projector in which the 
colors were changed for use at its previous site, but are not ideal for yours. 
The recommended first step in achieving such consistency is to use a color meter to 
measure the native primary colors—red, green, blue, and white—as they appear at the 
screen and record these as Color Primary Settings in the Service menu (password 
protected) for each projector. On the basis of these new values, which are stored in 
memory, each projector will then automatically calculate any necessary corrections to 
reproduce the original factory colors under the current environmental conditions. This 
essentially calibrates a projector to its surroundings, compensating for factors such as 
screen type, lamp and/or ambient lighting that can alter the final color characteristics 
on-screen, and will improve color accuracy and consistency in a group of projectors. It 
ensures a good starting point for further customizing and matching. 
To return to the factory-set color primaries, such as when a projector is moved to 
different site, you must access the Service menu (password-protected). Select the 
3.10 Using Multiple 
 Projectors 
 Matching Colors 
 In Multiple Screens  
						

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Factory Defaults option in the Color Primaries submenu. Then repeat the calibration 
process describe above, if desired, and continue with matching of colors. 
Color Adjustment Procedure 
Once the Color Primary Settings are calibrated for the site (see above), use the Color 
Adjustments by X,Y or Color Saturation menu to further refine each projector’s 
fundamental colors so that the hue and intensity of each color appears the same from 
one display to another. Once matched, you will have created a single new shared 
range of colors or “color gamut” that all of your projectors can produce. This 
palette—named User 1, 2, 3 or 4—can be applied or disabled for a source at any time 
throughout a bank of adjacent displays, simplifying both the setup and maintenance of 
a “seamless” wall. 
1.  Set up and optimize all projector settings. You can ignore color temperature, since 
you will be redefining color performance in this procedure, but do optimize each 
projector in every other aspect. Closely align all screen edges. 
2.  Assign projector numbers to make communications easier. Use a wired keypad. 
3.  Use the same lamp mode for all projectors, and do the following: