3 : O p e r a t i n g t h e P r o j e c t o r
CHRISTIE INC.
CHRISTIE INC. - -
35/70 Service/PM Manual
July, 1997
O P E R A T I N G T H E P R O J E C T O R
Although film projection using the show controller requires no operator intervention, certain procedures must be followed
to prepare the film and projector for playing shows. This section describes the setup and operating procedures.
Marking Shows on the Film
Reflective tape must be installed for each show on the film reel. Up to three pieces of tape per show are required:
•
BOF indicator
•
EOF indicator
•
SHOW NUMBER indicator (optional).
Thus, if three shows are used, nine tape strips would be installed.
The BOF sensor is located next to the “inboard” (away from the user) film perforations, while the EOF sensor is next to
the “outboard” (toward the user) film perforations.
Tape should be placed on the emulsion side of the film, as it might not be read through the film if it is positioned on the
base side. When a start command is given, the film accelerates to cine speed before it encounters the BOF marker. The
film decelerates to a stop after the projector detects the EOF marker.
The projector determines the show number by measuring the length of reflective tape, placed on the inboard side directly
opposite the EOF tape, with the BOF sensor. The show number tape is measured in units of frame lengths. For example,
show number two must have a tape length of two frames. The EOF tape opposite the show number tape must extend
beyond both ends of the show number tape.
If the projector is to automatically open the douser, by use of the
AUTO DOUSER
command (See Section 2.8.37), the
BOF marker on the film must be positioned so that it is 3 seconds before the first frame of picture. The placement of the
BOF tape can be calculated by multiplying the frame rate by 3. This will give the number of frame position, before first
frame of picture, for the BOF tape
