The history of Cinemascope

Ever since its first stirrings in the 1920s – when French inventor Henri Chrétien developed and patented his film process called ‘anamorphoscope’ – and on through the format’s true birth in the 1950s, CinemaScope has held its own as a format in an ever-changing world. However, in the America of the 1950s, TV was eating into cinema’s audience. Studios and cinema owners needed a new weapon to impress audiences. Spyros P. Skouras, president of 20th Century Fox at the time, green-lighted the creation of CinemaScope movies – the first one being the classic sword and sandals epic, The Robe. The format was a hit, delivering an experience movie fans had simply never had before. And the cinemas loved the format, because it was relatively easy to move over to the new system – all they needed to do was fit an anamorphic lens onto their existing projector. Plus, as a technician was always on-site,
maintaining and aligning the projectors was no problem at all.

Have you seen the video?

This video explains how other manufacturers handle cinemascope but more importantly shows the various benefits of Barco Residential’s approach to projecting cinemascope content. At the end of the clip we present our CinemaScope models..

Today's challenges

Until a few years ago, there were only two options for achieving a cinemaScope image:

The anamorphic lens route

An externally mounted lens slides in front of the projector (and back out of the way when not needed) The projector must vertically stretch the image and thereafter the lens will optically stretch the image horizontally to fill the screen. This system is complex, time consuming to install and has potential mechanical drift issues.

Memory zoom option

Using memory zoom results in a disruptive experience as multiple user interactions are required.

178 content in 235 lens mode no scaling jpg

The projector must zoom the image out to fill the screen whilst adjusting focus and shift. This approach is slow, taking up to 20 seconds before the image is displayed correctly.

The premise of the memory zoom option is that the projector needs a zoom range that can accommodate a 16:9 film and then a 2.39:1 movie by zooming the image as far as the edges of the black bars.

Installers today offer both options, but they have a few drawbacks:

1. Anamorphic lenses and the ‘constant height’ option can be problematic, because the integrator has to return to the site to adjust the inaccuracy in the anamorphic lens or the lens memory positioning.

2. The image quality will be negatively impacted when using an anamorphic lens by such things as chromatic aberration, pincushion distortion, focus uniformity and a softening of the image.

3. Finally it’s worth noting that a 2.39:1 image will be 32% less bright then an image in 16:9 when using memory zoom. Compare this to the Barco Residential approach which offers Constant Light Output and which, for the installer, means: no extra lenses, no fuss and no need for repeat calibration checks.

Formats & Resolutions

Most movies that are released in commercial theaters today are in 2.39:1(2.40:1) format. (People still often call this format 2.35:1 but in fact that format has not been in use since the 1970s when the standard was changed to 2.39:1).
The term ‘CinemaScope’ is used for all of these different versions, despite the technical differences. Important for the home market, of course, Blu-rays are released in 1920x1080 (4K Blu-rays are 3840x2160, with an aspect ratio of 16:9 (1.77:1).

However, when they release a CinemaScope movie, they end up using a 1920x800 (in 4K: 3840x1620) resolution for the actual picture. The full image is still the true CinemaScope 1920x1080 (in 4K: 3840x2160) resolution – but due to the limitations of the approach used, part of the image is shown as the dreaded black bars. If you increase the resolution of the display to 2560x1080 (5120x2160) and show the same native content, the viewer will see the same black bars at the top and the bottom, as well as black bars on the sides.

How does Barco create Cinemascope?

This is where Barco’s technology comes in: on Barco projectors, the image is scaled diagonally, using simulation grade processing power – a uniform process that maintains perfect geometry while utilizing more pixels, almost 2.7 million. The result is an image that fills the entire 5120x2160 space available – real CinemaScope! We refer to this as ‘cropping’, and there are several features under the cropping function in the menu. The procedure crops off the black bars over and under the image and changes the aspect ratio to CinemaScope. At Barco, we scale an image so that it fills the complete height of 3840x2160 pixels; and then, to maintain the aspect ratio, the image is scaled sideways to fill tthe full width. We do this in one step, as diagonal stretch.

Auto Aspect detection

The CinemaScope series projectors have a unique automatic aspect ratio detection function. It will detect the content aspect ratio and automatically scale the image to fit the required resolution in this case 5120 x 2160 and of course change back to 16:9 (3840x2160) if you have content in that format. Where required, clients can manually override the auto aspect detection/switching system and recall a specific, or custom format of their choosing.

This function also changes the aspect ratio when a scope format movie has menus outside the active picture frame (as shown in the illustration on the right). When hitting the menu button, or changing to 16:9 movie content, the projector automatically adjusts the image shape. You can also, as mentioned, switch manually between the different formats through onscreen or remote control commands.