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Multiformat Telecinies



Dick Hobbs wrote :

>> like Spirit - a high definition telecine
>>with output resolution converters to get other standards

I think one slight difference between the Sony machine and the Spirit needs to be clarified. the Sony machine relies on frame capture CCDs which will be 1920 X 1080 frame sensors which are physically manufactured for a 16X9 aspect ratio. Therefore, regardless of the final output this has to be derived from a 16:9 aspect ratio ( interlaced ) HDTV image, and the vertical scanning resolution is limited to 1080 lines. 

What happens with Cinemascope images ? - this has the tallest frame height, and is not  physically shot on the film in a 16:9 aspect ratio - therefore to get a one for one pixel mapping of the image onto the sensor would require anamorphic camera lenses - and then it would be a 2.35 image mapped onto a 16X9 sensor - still not a fit - something has to suffer in terms of resolution horizontally or vertically depending on how Sony intend to do this.

Using 2 dimensional scanning is valid - as long as the image on the film is shot in 16X9 and you get a one for one mapping ratio. Any other film aspect ratio would either require optical correction via the projector lenses ( expensive if a lens is needed for every film format ) or correction in signal processing - which will loose resolution.

The Spirit is a line array machine, and therefore only limited in resolution in one direction - i.e. horizontally the maximum scanner resolution being 1920 horizontal pixels. We are not limited in the vertical domain and in fact scan in excess of 1800 ( progressive ) lines vertically for a cinemascope image. 

The Spirit is not a just a *HDTV telecine with format converters* - this would imply the scanner resolution is only 1920 X 1080 - when in fact it is not limited to 1080 vertically.

Also to clarify the statement of Mr. Jim Mandrella - the Spirit will offer additional DTV format compliance and this will be available later this year. We will initially support 1280 X 720 in 30P and 60P ( with pull down ) 24P will be added when there is a standard for it. 480 progressive will also be supported again in 30P and 60P ( with pull down ) and 24P added later.


Steve Russell
Marketing Manager - Film Imaging Products 
Philips Digital Video Systems Co.


 


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