Conforming Original Camera Negative to Video Edit
In the old days (the ‘80’s and before) many of us independent filmmakers dreamt of making a 16mm blowup to 35mm film. If we were blessed, we shot Super 16 and hopefully also could afford a flatbed Super16 editing machine. We spent years courting the 2 New York labs of the times, TVC and DuArts. Blowups were expensive and averaged $30,000 or more for a feature. The rule of thumb was to shoot a half stop or more overexposed (hot) to burn out the huge grains. Blowups increased contrast so it was also best to shoot a 16 camera negative with as little contrast as possible. The dark shadowy areas were nearly indistinct in the picture and some labs developed ways to help increase shadow detail. I learned making a 16 dupe negative (most often people would blowup to 35 at this stage) from my camera negative before making a 35 negative helped to reduce the focus of the grain. This way I would get a better “film look” projected image in the final 35mm release print. There were so many tricks to learn on the road to Sundance and Cannes.
We now enter the HDTV era. Many in the industry today are asking, “Is film dead?” The era of digital exhibition will arrive later this decade. What advantages does HDTV or DV give the filmmaker over 35mm film? Many high-end DV cameras have 700 (16:9 aspect ratio) or 900 lines (4:3 aspect ratio). Not all DV cameras are this good a quality. HDTV cameras supply a signal that is approximately 1080 lines of vertical video. That is not true with all HDTV cameras. The other issue is with frames per second. Recently 24p cameras (www.24p.com) have been released that shoot at 24fps, the same speed as film projectors in theaters. The majority of features shot in the past few years used cameras that are 30fps. The 30i cameras using 1035 vertical lines (most similar to 1:1:85 aspect ratio of today’s theater screens) and transferred to 35mm film using 60 fields per second and the Sony M-Mode Transfer process gives the viewer an image that has the “film blurred look” of a stock shot on 35mm film. Most lab technicians agree that lower end DV (Sony 1000) masters transferred to 35mm look similar to 16mm blowups.
Let’s take a closer look at NTSC video and its 60 fields per second. NTSC at 30 fps is a standard in the video industry, but what does 60 fields actually mean? James Tocher, manager of the Vancouver, B.C.-based Digital Film Group provides an explanation:
“The nature of interlaced video is actually 60 interwoven fields per second; 30 fps in the sense of individual frames do not actually exist in interlaced video. This is partly a good thing however as it turns out for us in the way that our process of getting 60 field / second video to 24 fps film. That is because we utilize all 60 fields in a blended fashion to make 24 fps. Each field of video represents a part of the captured motion which is critical to the perception of smooth movement. As you know, in film, even though you have less frames, the blurring that occurs when something is moving actually helps the perception of smooth movement also. We mimic that blurring effect in our process to create a progressive looking frame in the end that has the resolution of the all the fields represented and yet still appears like a solid progressive frame.”
Sound is major when considering this kind of transfer to 35mm film. When you go from 30fps audio to 24fps, there will be approximately 5% difference in sound pitch. Often, sound for these projects is recorded on a DAT system. It is critical when recording with a DAT to have a sync generator outputting video black in HDTV. If you don’t do this, you’ll have problems later with sync. You still can use your recorded sound on camera as a reference backup, but it won’t be in sync with your DAT recorder unless you output a reference black from the camera to the DAT. This can be done using a wireless transmitter or with a cable. One reason for recording on a DAT is control and avoidance of this pitch problem. You’re still going to have to correct the pitch of dialogue to match theater specifications but all this will be done in post.
There are many philosophies on lighting DV or HDTV for a blowup to 35mm. Many DP’s (or DOP’s) say to light the same way you’d light to do a 16mm blowup, which means reducing contrast and increasing shadow detail. With this method, common throughout history of film, you’d expose for the blacks to capture as much shadow detail as possible. Recently, DV and HDTV DP’s recommend exposing for the whites, as the blacks will take care of themselves. The amount of detail which HDTV holds in the shadows is amazing--about 6 stops. This is opposite of our experience shooting analog video and film. New rule of thumb: with digital video, underexpose!
Is film dead? Not yet, but there is more happening blurring the distinction between film and TV media.