It can be cumbersome at times to keep up with the ever changing world of digital cameras... Not only that, knowing which camera is the best and most current solution for your needs is not always apparent. As it stands right now in 2015, most feature productions have preferred using one of these three camera brands/models for several years now, marking these as the current champs in the world of cinema.
The 3 most used cameras in feature films to date are:
RED DRAGON 6K Digital Camera
This red-cam has been used in such films as Pacific Rim, The Hobbit trilogy, Guardians of the Galaxy, and many more. It seems to be a favorite for movies with heavy VFX (yet there is no data to prove that integrating the two is superior to the other cameras listed below). This probably has something to do with the innovative 6K Dragon sensor that captures over 9x more pixels than HD. Reproduces stunning detail and native exposure eclipse 35mm in both latitude and image density. This camera is able to shoot in super low light situations and keep the digital noise to it's absolute minimum. The RED Dragon also shoots high speed up to 100 fps in 6K, all the way to 300 fps in 2k and everything in between. Boasting many other valuable features that we don't have time to discuss, this camera is a serious contender in the ring of Cinema.
ARRI ALEXA XT Digital Camera
This AMAZING camera has been used in such films as Life of Pi, the Hunger Games, and many more. -- The ARRI Alexa XT has been fitted with superior technology that allows it to capture organic looking imagery that closely resembles the motion and exposure of film. This is partly due to the Super 35 sensor with Open Gate and 4:3 sensor modes coupled with the High Dynamic Range of exposure and ARRI's color science that allows it to resolve mixed color temperatures and reproduce natural skin tones and color. The Alexa performs extremely well in low light situations as well as having a wide range of frame rates and options for data capture. It's no wonder why this camera is a favorite among many who wish to reproduce the look of film using digital technology.
SONY CINEALTA F65 Digital Camera
This robust camera has been used on such films as Oblivion, Evil Dead (2014), and many more. It's becoming a favorite among some and for logical reasons too. It might have something to do with the 20 megapixel Super 35 image sensor that allows it to be the highest resolution camera on the market and is unrivaled in there ability to reproduce scene detail and texture. This cameras resolutions range from super-sampled HD and 4K to 6K and 8K, allowing a wide range of options for all kinds of productions... especially ones with the future in mind. The F65 performs wonderfully in low light and also comes equipped with high speed up to 120 fps.
These 3 camera's are some of the best cameras on the market right now for digital motion picture production. Not only that -- digital cameras period have come a long way in reproducing the natural look of film and it's exciting to see these companies working hard to give the audience what they want to see at the theater house.