Sound, Soundtrack Restoration and Distribution of Beyond the Rocks (1922) - Text 2
Technically, the stretching could have been done in two ways, either by creating new frames as interpolations of the existing ones or by doubling existing frames. Based upon test results, in the case of Beyond the Rocks, the latter was chosen as interpolation led to the creation of weird looking frames that were not acceptable. On top of that, from an ethical perspective, creating new frames, even though by interpolation, means adding images to the film that have never been there and could easily be mistaken for original frames. If badly documented, these interventions could also become irreversible. Differently, the stretching process that was chosen in the end, namely to double every third frame of the film, going from 18 to 24 frames per second (i.e. 123345667899…), is both detectable and reversible. The drawback of this choice though is that a stuttering effect can be noticed in projection. In reality, only an expert eye will notice the stutter, which becomes more visible in combination with lateral movement within the image and with panoramic shots.
Finally, a different path for simulating the original tints was followed in the creation of the hd master meant for the digital projection, the DVD release and the television broadcast. As the Desmet method, a photochemical process, was used for making the film prints, a digital process had to be applied for making the digital versions. Here color filters, simulating the original tints, were added digitally to the black-and-white digital image.
