Film-Tech Forum ARCHIVE: Why don't new digital 4k cameras match DCI spec?

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Posted by Lyle Romer (Member # 1266) on 07-19-2007, 07:01 AM:

I was looking at the specs for the RED one and Dalsa Origin and something doesn't make sense to me. The DCI spec for 4k is 4096x2160 (with scope 4096x1716 and flat 3996x2160). I would have thought that if a 4k camera was being designed, the imager would have the same resolution.

However, the RED one imager is 4520x2540 active pixels and the Dalsa Origin is 4000x2048. The output of either of these cameras will have to be scaled for the native resolution of 4k D-cinema projectors. In that respect I guess the RED one is better because it is higher native resolution.

Why on earth wouldn't they have designed the imagers to be 4096x2160 with the physical dimensions of a Super35 frame?

I assume in the case of the Dalsa, the pixels are too big to fit so they reduced the resolution in favor of frame size matching Super35 but the RED one they could have designed bigger pixels (which you would assume to have better dynamic range and signal to noise ratio).

Posted by Mark Gulbrandsen (Member # 72) on 07-19-2007, 11:03 AM:

quote: Lyle Romer
Why on earth wouldn't they have designed the imagers to be 4096x2160 with the physical dimensions of a Super35 frame?

The Panavision Genesis and Arri D-20 both have a Super 35 sized sensor and do translate right to Super 35. I think you will alwaws be seeing a push to increase the resolution of the imager chip no matter what end result is actually needed. That extra resolution will translate onto film better anyway. Scalers can do the work to get it to where D-Cinema needs it. Hopefully we will also see constant progress in getting higher resolution into cinemas as well but expect that to take decades whereas cameras will make have always made huge leaps every few years. I believe that in just a few years you'll see those numbers double!