5
Adjustment of the two light sources
Adjust the analog LED
Alignment
Preliminary:
Because you are dealing with two soundtracks, and because you
are starting from scratch, you will have to go back and forth
between the two media while you get everything optimized.
Mostly, this means the
adjustment of the two light sources
.
The good news is that as already mentioned, the two optical
assemblies have been preset so that you have a beginning point.
Their focus and azimuth may not be exactly correct for your
sound head, but they will be close enough to get you started.
Loosen the clamp screw of both of the copper LED mounts until
they can be moved easily, but will stay where you put them when
you let go. It is easier to grab both of the mounts when doing the
analog LED (which is the inner one), and so it is best to do it
first.
Analog:
Adjust the analog LED
by eye until it looks as though it is
opposite the lower lens. In the cinema processor, turn both the
level and high frequency adjustments all the way down so that
both channels will be essentially identical. Thread a loop of
Dolby Cat. No. 97 (a very convenient method is to make a loop
of 1/2 Cat. No. 97, and 1/2 “Buzz Track”) and look at it on your
oscilloscope just as you would for a normal “A” Chain setup.
