Monday 29 April 2013

Digital Cinema – Film vs. Digital Print


       We all know that movies are very powerful in terms of financial strength and the impact it has on the society. This multi-billion dollar industry started blossoming in 19th century. If ‘talking cinema’ (i.e. visual with audio) is taken as birth of cinema then it was in the year 1927. The name of the movie is  The Jazz Singer [1]. Nearly for a century movies were shot on film and it was developed with photo-chemical process. Projectors were used to rotate the film reels in a constant speed in front of a powerful lamp. The images created were projected on to a silver screen. People sitting on the dark enclosure were amused with the pictures shown. At the end of 20th century speech, audio, image and video were digitized. Slowly the ‘digital wave’ started engulfing the film technology. In this post, we will have a comparison between film and digital content.

The stakeholders of film are Actors, Technicians, Producer, Distributors, Exhibitors (Theatre) and Audience. One has to know the way movies are produced and role of each stakeholder in movie making process to understand the necessity for digital migration. Director of the movie makes the film on behalf of the Producer. So the right of movie lies with producer or Production Company. Region wise distributors are selected based on bidding and right to screen awarded to them for few weeks. Distributors in turn make contract with exhibitors to release the film in their region.

Movie making is made up of three stages: Pre-production, Shooting and Post production. Pre-production stage deals with story selection, screenplay and actor selection and signing contract with them [4]. Shooting is where movie scenes are shot with actors in various locations. It is a very time consuming process. A scene that lasts for minute in movie, Indian directors spends at least a day. Post production is much more time consuming process. Here raw footage that is shot in various locations is processed and arranged into a feature film.

Every day after shooting today’s footage is readied in the Lab for filmmakers to view. This is called dailies and in outside US it is called ‘rushes’. This acts as a feedback for director and camera man. In the Lab, raw footage is made into negative. Then they perform colour correction on negative but it is called as timing. Negatives are rearranged and if required cropped by director with the help of editor. This process is called as editing. Most of the time visual effects (VFX) scenes are added to make the movie worth watching. Actors jumping from 10th floor and other heroic stunts are possible due to VFX only. Then sound is processed and converted into optical signals and stored in twp sides of the film. Cropped and selected negatives are called ‘Cut Negative’. From the cut negative, ‘Answer Print’ is produced. Around 3000 release prints are developed from answer prints for world wide release. Regional movies will have at maximum 400 prints [4].

Star Wars Episode II : Attack on the Clones was the first
 movie fully shot  on  digital camera.  It was in the  year 2002.

Pros of Digital print
  • Cost of 35mm film print is around €1,500 but the cost digital print that is stored in computer hard disk is only €150 [3]. The cost reduction is substantial when the number of release prints is high.  This forces producer and distributor to embrace digital print.
  • Unlike film, making a new copy of digital release print is easy and economical. This feature makes piracy market to thrive well. To combat this encryption techniques are extensively used.
  • After several screening, film prints gets into wear and tear. In old film prints lot of scratches will be visible and it will annoy the viewers. This will not occur in digital print.
  • Proliferation of TV and DVD on homes started reducing movie goers. To retain the flock directors were forced to make visually stunning shots. When these shots are seen on a standard definition television (simply old CRT TV) they are not impressive. This forces audience to throng movie halls. Nowadays lot of Computer Generated Imagery (CGI) used in VFX. The best example is Steven Spielberg’s Jurassic Park. By nature CGI is digital.
  • Proliferation of Non linear editing. Earlier days at the time of editing negatives physically cut and spliced together.  In TV production they use few video players that are loaded with same raw footage. The first cut will be played from one player and second cut from another player and so on.  To change a cut one has to just change video players start and stop time. This helped making changes easy and after finalization cuts were copied into new video cassette.  As the process is non-destructive, original negative is preserved well. Slowly this technique was adopted by movie industry. If the negative is in digital form then it will much easier to perform on a computer.
  • Post production process time can be reduced considerably if film makers work on digital format. The level flexibility digital offers are really high. 
Pros of film print
  • Film is a proven and mature medium. 
  • Film equipment availability is not an issue and they are economical.  
  • 35 mm film is accepted as a movie standard worldwide. We have 16 mm, 8 mm formats also.
  • Even today, a century old 35 mm film stock can be projected on a silver screen any where in the world with the existing projectors. This is amazing when we consider the fact that two decade old software files are nearly unreadable. Thus the information is lost altogether.  
  • Huge amount of film stock is available as archives. So equipment's like projectors should be made available to protect and preserve the archives. Conversion of film archive into digital format and indexing the digital prints is tedious and capital intensive.
  • Raw footages are scanned and made into digital format called  Digital Intermediate (DI). All the post production process is carried out on DI and at last release print is made in film. This technique combines the benefits of digital format and robustness of film. 
  • Film projectors are cheap compared to digital projectors. If there is malfunctioning of film projector then either projector operator or local mechanic are capable to rectify them.  In digital projector company service technician has to arrive and rectify the malfunction.
  • 35 mm has more dynamic range, colour gamut compared to digital print. Analog projectors can project colour films with density range 5.0 which is equivalent to 17 stops [5]. Digital projector yet to arrive to match this feat.
  • Film does not have the problem of defective sensor or thermal noise problem. This problem in digital media arises because of underlying technology (CMOS or CCD) they employ.
All the points supporting film is taken from [1].  One will conclude the fight between film and digital is really tough. But the day will come when digital print reign supreme.

References 
  1. Brian McKernan, Digital Cinema, The revolution in Cinematography, post production and distribution, McGraw Hill, 2005.
  2. Charles S. Swartz (Editor), Understanding Digital Cinema : A Professional Handbook, Focal Press, 2004. (ISBN: 978-02408-06174) 
  3. Digital Cinema in Ireland, A review of possibilities, http://www.irishfilmboard.ie/files/reports/Digital_Cinema_in_Ireland.pdf, (PDF, 1510 KB)
  4. Private discussion with an VFX expert working in Prism & Pixels VFX Studio, http://www.prismnpixels.com
  5. Archives and digital cinema, http://ec.europa.eu/avpolicy/docs/reg/cinema/june09/archives_dcine.pdf (PDF, 361 KB).

Three Musketeers - Appendix

Earlier post dwelt on aperture, ISO and shutter speed. After posting it, I got following website.


Figure 1. Various aperture size
I failed in earlier post, to put a picture like above. I hope figure 1, makes easier to visualize aperture size. I have searched lot of webpages regarding shutter speed, ISO and aperture size. All the webpages give theory and at  maximum they may provide few images. But in this website they allow the user to interact with the images and get a FEEL about  shutter speed.  In figure 2 they provide three options Slow, Medium and Fast. User can select any one and find the corresponding result. Lot of examples like this. Please visit.

Figure 2.  Shutter speed with three options. Here Slow and Fast option is selected