70 mm Imax, 35 mm, 2K or 4K Digital: Which is the better movie format
by Stephan Jukic – November 25, 2014
When new movies come out, and especially big budget “blockbuster” movies, they often hit a lot of different theater screen types and in the process, lots of words such as Imax, 70 mm Imax, 35 mm, 4K and 2K get thrown around as part of the theaters’ promotional efforts.
Naturally, this can become very confusing to audiences who don’t know a lot about movie projection technology and the question of which screen type is best often arises.
Here is a breakdown of what’s what.
33 mm film is the classical old projection format used for decades before the advent of digital projection. While the detail of 35 mm film is immense (about 8k) when digitized to full levels of detail, the actual projection capacity of film projectors that show reels of 35 mm is much less than that and in real terms, a 35 mm print being shown in a celluloid using theater screen is showing 10 times less resolution than 70 mm Imax (more on Imax shortly).
On the whole, 35 mm movie theaters are becoming less and less common in the U.S as a lot of film production studios themselves switch over to digital filming from using celluloid.
Imax 70 mm on the other hand, is the very best that cinema projection has to offer. 70 mm Imax screens are still a rare animal in most of the U.S and even more so internationally but where they are to be found, they offer a grade of resolution, color, picture clarity and sheer square footage of screen size that isn’t rivaled by anything else in the industry.
70mm Imax projection also beats out 4K projection in terms of sheer resolution, creating something closer to 8k in quality. However, for movies to be displayed on an Imax screen in a truly effective way, they also have to be captured with 70 mm cameras, which is also not the most common of occurrences. However, one recent example of this is the movie Interstellar, which had parts of its length filmed in 70 mm, of which director Christopher Nolan is a big fan.
Finally, moving onto 4K and 2K, we come to digital theater projection technology of two different total resolutions. 4K projectors fill the theater screen with 4096 x 2160 pixels of resolution amounting to a total of just over 8 million pixels and 2K projectors do about half of that (hence the resolution’s name).
Most modern movie theaters currently use 2K digital projectors and more and more are switching over to 4K projection. When it comes to theaters, this is a good thing, because while on a TV screen the difference between 2K and 4K might be very hard to notice except at extremely close range, it is something that’s highly visible when viewed on something as big as your typical cinema screen size.
However, 4K projection technology also requires much more lighting in order to be effective and the screen itself needs to reflect light better in order to really bounce back that extra projector lighting. This is measured in terms of coatings on theater screens called “gains” With 2K or HD projection technologies, most cinema screens were only one gain. Now, with the advance of 4K projectors to many parts of the U.S and other countries, many screens are being changed over to 2 gain and even 3 gain versions, something which is also effective for 3D movies which also require plenty of lighting.
Ultimately however, these assorted details of screen resolutions and projection types are largely academic. While the difference between 70 mm Imax screens and just about anything else truly is noticeable, most audiences will enjoy a good movie equally whether they view it on a 2K 35 mm or 4K screen.
Story by 4k.com