Tape-to-Film Transfer
The recent successes of films such as The Blair Witch Project, The Cruise and The Celebration has generated a great deal of interest in tape-to-film transfer techniques. Although absolutely a viable option, a tape-to-film digital transfer is technically complex and tricky. If you exercise sufficient care, it is possible to finish your transfer with a final product that is nearly indistinguishable from the original.
The following list of postproduction formats is ranked in order of quality:
1. Film Origination and Digital Component Post (D-1)
2. Film Origination and Digital Component Post (Digital Betacam)
3. Film Origination and Analog Post (Betacam)
4. Video Origination (DV)
Your greatest enemies are video artifacts. Many of the suggested techniques listed here are designed to prevent them. Keep in mind that many of these artifacts will not be visible on your computer screen or video monitor. The theater screen is exponentially larger—flaws that are barely noticeable when editing can become glaring errors on the big screen. Also, the higher resolution of the film print--which usually works in your favor-- now works against you. The film print will not be nearly as forgiving with your lower resolution video cut. Following these techniques will prevent expensive (and not always effective) postproduction "fixes" and yield the highest quality film print possible.
The first tip may seem obvious but it is a common mistake: shoot your footage at 24fps. The default camera speed of video is 29.97 fps but if you plan on finishing on film, you need to change that to 24fps. This eliminates the need to deal with 3:2 pull down, a messy and imprecise conversion from video to film.
On the same token, when preparing an NTSC project exclusively for film finish, transfer and edit on whole frames keeping one film frame on one video frame. This will avoid adding the 3:2 pull down. However, when viewing your video, remember that it will be sped up. You will be viewing material at 30 fps that is meant to be projected at 24 fps. PAL presents no problem in this area since it is at 25 fps and is very close to the final 24 fps projected rate.
In addition, render all graphics and animation at 24 frames per second. Normally, this means that the graphics must be generated in cine-compressed mode, to be expanded later and integrated into the video.
Avoid noise reduction and manipulation of your video. It may be tempting to do your own color correction and special effects but unless you have access to a high-resolution workstation (FLAME), don’t do it. The more you manipulate colors and add layered effects with animation and editing software, the more punishment you’ll receive with regard to clarity in your final cut. If you are capable of using your DVE for high-resolution manipulation (e.g., dissolves, DVE moves, color timing transitions), it should be on whole frames within original film frame boundaries. The following is only applicable if you are originating on film: each video frame is created with two interlacing fields, which creates difficulties doing exact matching, frame to frame from film-to-video. Telecine transfer and all edits, cross dissolves, and composites should be at first field dominance.
Do not plan on creating motion effects in postproduction. If you try to create slow motion or fast motion effects in postproduction, you will introduce artifacts present in all DVEs. Create your effects in the camera at the time of shooting. Of course, at the present time, this is only possible with a film camera. In order to have slow motion, you need to increase the number of frames within a given shot. Over cranking your camera means that more unique frames are captured during that specific shot. Creating those frames with a DVE means that the machine tries to calculate which existing frames to duplicate in order to slow the motion down, which often creates composite frames. This jerky substitute that passes for slow motion suffers from a great deal of field-based video degradation that will be obvious in the film print. The finest results are obtained if speed changes are performed on whole frame boundaries by adding or dropping whole frames.
Changing the size of your frame should not be accomplished on your DVE. This is the common theme throughout: most DVEs and all their wondrous effects cannot be used if you plan on finishing on film. The loss of resolution and sharpness will end up killing you in the transfer. If you originated on film, sizing changes (reductions or enlargements) can be accomplished with little loss at the time of telecine transfer by optically enlarging or reducing.
Keep your eye on the vector scope. Yes, there is a reason why video engineers get upset if the levels aren’t on target. Keep your video levels for RGB below 100 units or they’ll be clipped off on the film. Also keep a careful watch on your black/white levels to avoid muddy blacks and blown-out whites.
When creating titles, avoid saturated colors (red) with sharp edges. Again, this is a problem created because video simply does not have the resolution of film. Encoded video such as D2 or 1" tape is especially sensitive to this. Also, as with speed changes, graphics should be created on whole frames, and animation or moves on graphics should be performed on whole frame boundaries.
Excerpted from: http://www.24fps.com
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