The movies that our parents and grandparents watched were not on digital media, but on analog media such as film, which little by little are degrading over time, which requires their conversion. What is the cost to convert 8mm, 16mm, 35mm or even larger capacity spools? whatWhat resolution are old movies equivalent to? If you want to know, then keep reading.
Traditionally, the cinema was recorded in film format, these are reels that store in each section of it the frames of the film that was projected at high speed in theaters. For years domestic users used cameras with 8mm tapes, while in the cinema they watched films recorded in 16, 35 and even in some cases up to 50mm. However, we tend to think that the movies of yesteryear are recorded at a lower resolution, just because they are older. That is why we have decided to talk about a topic that is out of the ordinary in HardZone, but that has a lot to do with the evolution of hardware.
From film to pixels, is this how old films are converted to digital?
The digitization of old films became an obligation for distributors from the moment that data storage and digital video reproduction media allowed it. Especially due to the fact that the film degrades over time and ends up losing the original color and the reel can even be completely lost over time. Now, the process is not as simple as it seems and it has its associated problems.
The concept of even lines per mm
A frame of a 35 mm film is 36 mm wide and 24 mm high, that is 864 mm2 in total, but we need to capture the difference of the pigments in the film. Therefore, we cannot make the association that each millimeter is equivalent to a pixel since we would not have enough information, but we need to increase the size of each of the frames as much as possible to get all the information possible.
Well, in the film the resolution is not counted by pixels, but by what we call even lines per millimeter. That is, the number of black and white lines that can be distinguished, either by eye or through some type of optical sensor. So in the end each of the lines can be identified as a pair of pixels. Which will help us in the digitization of the frame. However, at the time there were various types of resolution in this regard and in the end it has been necessary to create a standard resolution for conversion to digital.
Thus, a 35mm film by today’s standard converts each frame to 4096 x 2160 pixels, a 16mm film to 2048 x 1080 pixels. Note that these resolutions are very similar to television resolutions, but they are not exactly the same. . By the way, today we have film directors like Quentin Tarantino or Cristofer Nolan who record with 70mm film, which translates into a resolution equivalent to 8K when digitizing.
How much is a film in megabytes?
Digitizing a film means having to store it on a computer storage device, be it an SSD or a Hard Drive. Although the versions that come out domestically or via streaming will have a lower resolution than the master copy and will be derived with worse quality, it is necessary to preserve the film in all its original splendor for future releases so that it is not lost.
The good thing about keeping data in digital is that the material is not degraded, the bad thing is that when working with discrete data we need a large storage capacity and that is why old movies, despite the fact that we receive them in compressed video codecs for distribution through streaming platforms or for sale on disc.
For example, let’s assume that we want to make a digitized version of Titanic and that it was recorded on film. It is a film that lasts 194 minutes and was recorded in 35 mm, if we do the pertinent calculations we will see that each raw frame of said film occupies 25 MB, in one second there are 24 FPS and it could be double if it had been recorded in stereo for 3D cinemas that did not exist at that time. Total that in a second you end up having 607 MB of busy information and a minute is stored in 35.59 GB. Therefore, the final film in its digitized version without losses compared to the original film, would ultimately occupy 7 TB of storage to save the visual information and that without counting the audio.