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4K resolution
Refers to approximately 4,000 pixels of horizontal resolution used in several digital formats for shooting the highest-quality video or scanning 35mm frames. 4K movies can be used intact for digital cinema theater projection or downsized to HD and other formats. With the huge number of pixels captured in 4K resolution, scaled down images also retain more detail. Following are the 4K (and 2K) digital resolutions for common cinema formats.
4K
------------------------Horizontal---Aspect--Megapixels
Cinema Formats-----Resolution---Ratio----Per Frame
Academy Standard--3626x2664--1.37:1--9.7 MP
Academy Flat-------3996x2160--1.85:1--8.6 MP
Anamorphic Scope--4096X1714--2.39:1--7.0 MP
2K
Academy Standard--1828x1332--1.37:1--2.4 MP
Academy Flat-------1998x1080--1.85:1--2.2 MP
Anamorphic Scope--2048x858----2.39:1--1.8 MP