USL PSA-200U - Manual (Page 10)

Page 10 USL, Inc. PSA-200U Instruction Manual 1st Edition. October, 2004
OPERATION
This section describes the operation of
the PSA-200U in detail. It is organized by
specific activity for easy reference. These
activities appear in the usual order they are
performed when using the PSA-200U.
Automatic Alignment
Manually adjust the camera angle and the
camera zoom switch so that the theater
screen appears centered in the camera’s
viewfinder (see Fig. 3). Press F3, or click
on Camera View. The image should appear
centered in the laptop computer display.
Adjust the zoom control so that the edges
of the screen are visible in the laptop com-
puter display. Now press F2, or click on Auto
Align. The PSA-200U software will automati-
cally sense the edges of the movie screen
image and create an artificial border for the
luminance measurements. This border is a
rectangle inset from the screen edges by 5%
of the screen dimensions. All screen lumi-
nance measurements are made within this
border. NOTE: The Camera View, Luminance
and Spot Meter are the only functions that
use the alignment border.
Manual Alignment
In rare instances, when the lamphouse is
severely misaligned, the automatic align-
ment software will not be able to locate
the screen edges. In this case, the manual
alignment function must be selected. This
function allows the user to manually set the
borders of the screen area to be analyzed.
First, press F3, or click on Camera View,
then click on the “Alignment” menu, then
on “Manual.” Position the mouse pointer
on the top-left corner of the desired area,
then click and drag the mouse pointer to
the bottom-right corner of the area and
click again. The manual alignment border
and the previous alignment border will both
remain on the screen. Now select “Camera
View” again. A single alignment border,
representing the manual alignment, should
be present on the screen (see Fig. 4). The
manual alignment border that is produced
must lie inside the image and not in the
darker border surrounding it in order for a
manual alignment border to work.
(Fig. 4) Manual Alignment
Measuring Luminance
First, use the Automatic or Manual Align-
ment function. Next, press F4, or click on
Luminance. The PSA-200U software breaks
down the luminance of the projection screen
into 45 (9 X 5) zones (see Fig. 2). A separate
luminance value is measured and displayed
for each zone. Each of these luminance val-
ues is an average of 10 separate measure-
ments taken at different places in that zone.
The shading of each zone shows the relative
luminance with respect to the other zones,
giving a good display of the light pattern for
ease of lamp-house adjustment. Zones are
numbered, left to right, starting from the
top, for reference. The status bar (located
at the bottom of the screen) displays the
zone that the mouse pointer is in, along
with the average luminance and the center
zone’s luminance.
Measuring Illumination
It is possible to measure the incident light
reaching the movie screen by switching
from the “Luminance” mode to the “Lu-
mens” mode. The screen dimensions and
gain must be entered as described on page
15 (see “Lumens Mode” and Fig. 12). The
Lumens mode displays the total screen il-
lumination as well as the illumination for
each segment of the display on a 3x3 grid
or the 9x5 grid.