After having performed tests ,James Cameron believes that 1080* 1920p is better than a 35mm(IP):

James Cameron
"The amount of data available from a 35mm negative is much less than the amount of data available from an HD frame."

The Hollywood Reporter:

"Film purists argue the opposite. "

James Cameron:

" They're wrong. You can take an HD image and blow it up by double before you start to see the same amount of granularity you have with a 35mm negative. George Lucas did some tests that I flew up to see, and it corresponded to what we'd found. I'd say the Sony HD 900 series cameras are generating an image that's about equivalent to a 65mm original negative".

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