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Re: Noisey Transfer impossible Question.



Steven Gladstone commented on the TIG list:

>As I said the image in the monitor in the Transfer room looked very clean.
>However in subsequent Edits, and Dubs from the Digi beta the transfer was
>recorded on, there is What looks like Video noise? White dots, very small and
>in a fixed pattern seemingly strobing.
------------------------<snip>------------------------


Dealing with 16mm negative that's been exposed a stop under with a lot of
black area is not the best of situations.  *sigh*

But I know of no noise-reducer in my experience that would add small white
strobing dots to the image.  Typically, the effect you would see from
excessive Rank FGR (film grain reduction) or DVNR standard recursive NR
would be smearing.    Without actually seeing the transfer, I can't say
what you're seeing.  My gut feeling is that if this is not neg dirt, then
this *might* be noise in the Rank itself, being amplified under a
worst-case situation.  But I'm reluctant to criticize or diagnose a
transfer I can't actually see.  [I agree with Graham Collett elsewhere that
there may well be several problems going on here.]

My advice:  retransfer the selects actually used in the final without any
noise reduction, or at least with FGR only at a very low setting.  You will
get best results on a recent Ursa Gold or Diamond, or at least a machine
equipped with Twigi, which will help eliminate any residual noise in the
signal path.

Once the film is transferred, re-edit the entire project in on-line, then
do selective scene-to-scene tape-to-tape noise reduction on the edited
master tape (prior to titling).  For situations like this, I would suggest
settings of about +4dB on DVNR's ANR (adaptive NR) mode, plus maybe 6-8 dB
of Recursive NR -- but these are approximate numbers, and every situation
can and will vary.  If the image is very bright and is completely
surrounded by black, you're going to have to stay on top of the potential
smear problem very, very closely.  In very drastic cases, you might also be
able to reduce chroma from the low-lights (blacks), which will slightly
reduce chroma noise.  I would also be extremely careful with enhancement
settings.

I also know it's easy to say this now, but when in doubt, always overexpose
by 1/3 stop for video.  In 20 years, I've never experienced a situation
where this has gone wrong -- assuming normal developing and a working light
meter.

--Marc Wielage
  Complete Post/Hollywood



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