[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: RE: MKIII Auto shading



Graham Collett wrote:
> 
>    I've just put in our second one at The Machine Room, London. They do
> work well without doubt. The shading alone will reduce errors to less
> than 1% but will leave hard burn transitions. 
> We worked with shading only for a while, and that was fine except for
> fact that we were/are doing tons of 16:9 stuff. A 4:3 picture taken up
> to a 16:9 viewing a/r (in pal anyway) results in a one line CRT scan.
> So, our tubes reached premature death either by burning (the shading
> only didnt cover that up) or by the visibility of phosphor grain.
> We added the VTK burn corrector and the above symptoms were corrected
> for beautifully.

I've experienced similar problems here, again with 16:9 transfers.
However, I devised a circuit which automatically introduces a "focus
offset" a couple of minutes after the transport drops tension. This has
the effect of softening the edge of the burn, making it easier for the
burn corrector to deal with it, but has the advantage that it
<i>always</i> occurs regardless of whether the colorist remembers to do
it or not (sorry Colorists!). Naturally, as soon as the transport is
tensioned again the offset is removed and the chain snaps back into
focus.
If anyone wants circuit info., please contact me direct and I will be
happy to forward same.
Cheers,
Mal
-- 
"Digital doesn't mean better, rather the mediocrity is preserved"

Malcolm J. Todd,	email malt at omnicon.com.au 
Omnicon Video, 		Voice....+(612) 9439 6600
Sydney, Australia	Fax......+(612) 9906 3246

---
quick NAB telecine product focus at
http://www.alegria.com/tig3/TIGNABFS99.txt

Thanks to Laser Pacific/Leon Silverman for support in 1999
No advertising/marketing allowed on the main TIG.  Contact rob at alegria.com
anonymous messaging now at http://www.alegria.com/HyperNews/get/ubique.html
1022 subscribers in 41 countries on Tue Apr 13 17:15:22 CDT 1999 
subscribe/unsubscribe with that Subject: to telecine-request at alegria.com
complete information on the TIG website http://www.alegria.com/tig3/