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RE> Trouble with....A view on the Gold.............

With regard to Kens drifting Gold the symptoms he descibes are very similar to
those we have 
experienced here. One machine had serious colour drift which could easily be
measured by split
screen comparism over a 20min period.  As per David Bernstein the solution was
to replace the
PECs and more lately we have had to change the PEC bases in order to eliminate
noise. This noise
was dependent on PEC effort but for all the usual reasons was especially obvious
in the Blue.
In terms of operation we always keep the machines on 24hrs but the tube is off
overnight, however
short that may be!!  We then allow at least 1hr before the first serious auto
alignment to let the tube
warm up. The Gold runs very hot but if left with all doors on etc it is a
constant temp. One thing we 
have found useful between sessions is to lay a strip of clear exposed neg in the
gate to eliminate
the light from the low beam standby tube belting into the PECs for 1/2 or 1 hr
and causing them to
charge. This means that the grade applied to the first few images is consistent
and is not going to drift away as the PECs stabilise to the density of the

We find generally that the positional difference between run and still is now
more objectional than colour drift especially when working on commercials
involving multi layered elements. No matter
how carefully the tube is aligned a SMPTE res chart is not going to match shape
in run & still and
there is no pin cushion board to tweak.

The other area that presents problems is the shading. We are using the Pogles to
store base offsets
that bring the Golds auto alignments back to even shading but these can have to
be changed dramatically if we run Inter Pos stock for instance.

The general repeatability of the machines is average and the swapability of jobs
between rooms is not as smooth as it should be given the effort and money spent
in producing two identical suites. 
Having said that the individual pictures produced are very good and lend
themselves easily to further processing at  "high" colour resolutions in down
stream boxes. 

Seamus O'Kane
VTR Ltd London.