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RE>Re: Green Light and lower Colour Resolution





Thanks for this Bert,
Very interesting, but the main thrust of the thread was that at Film resolutions equal bandwidth is essential for high quality visual FX work.
This is a fact. We know Spirit is very nice at TV resolution.
It would be fun indeed to have a shoot out, deriving blue screen keys at Film resolution between Kodaks Cineon hardware and Spirit. This comparison would happen in an Inferno or similiar session and maybe something for the Flame user group.
You can however perform a valid a similiar test right now at your facilities .
Transfer a BLUE only smpte chart at 4:2:2 into Flame/Inferno and compare this to a 4:4:4 BLUE only smpte chart again fed into Flame/Inferno.
You will be staggered at how bad the 4:2:2 picture is, this is what the keyer has to work with and a clear example of reduced colour bandwidth.
Yes I know the pixel size is different but the difference is relative and valid.

> In telecine systems some bandlimitation in colour channels is helpfull
>because going through the non linearities of the CRT-Gamma >precompensation
>results in broader signal spectrum. Luma is less sensitive than Chroma
>against disturbances, ringing, etc. Same situation in analog and in
>digital.

Sorry Bert but this is misleading, no one wants less than equal bandwidth. At film resolution, there are no CRT's involved in the digital film chain on a Spirit to Laser recorder output. Please remember the thread is refering to using Telecines as Data Scanners in the Film VFX arena.

It's great to hear you on the TIG.
My interest is also picture steadiness on these machines when atempting to use them as DATA scanners. You seem to be the man with a  lot of first hand experiance on this subject. Any thoughts please?
Cheers
Paul

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