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Highdef Production
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Highdef production has similarities to both film and video production. Here are some points that will help when you go into production.
Camera
Highdef camera packages will generally be more expensive than comparable 35mm packages. Lens packages for both are comparable. If you only use a zoom in Highdef, you will save significantly, but you sacrifice the wonderful choices and greater range of focal lengths that prime lenses give you. The equipment rental costs of 35mm and Highdef become closer when you add video assist equipment to a 35mm package. Although rental companies deal on both formats, right now it is easier to make deals with 35mm than with Highdef. The real savings in HD come in tape stock costs, which are considerably less that film stock, processing and telecine which are necessary with film. As more Highdef cameras and formats become available, the equipment rental rates will be more comparable.
Highdef cameras are available that can shoot at 23.98P, 24P, 25P, 29.97P, 30P, 59.94P, 60P, 50i, 59.94i and 60i. The "P" is for progressive scan and the number represents frames per second (fps), and the "i" means interlace scanning and represents fields per second. On some cameras, the frame rates can be switched with menu settings and others are only single format (usually 60i). For 24P production, slow motion effects are possible with Highdef similar to overcranking in film. Panasonic's Varicam can capture at various frame rates from 4 to 60 fps onto a DVCProHD tape. Sony can generally match the look of 30, 48, or 60 fps in film by shooting in the various modes. Each of these systems requires special post production processing to convert the footage to 24P as slow mo.
The most common highdef camera capture device is a CCD which is 2/3" in size. This size limitation creates a large depth of field in relation to the lenses, so it is a bit more difficult to get selective focus shots in HD than with 35mm film. Using neutral density filters to lower the f-stop will help, along with using faster prime lenses and longer focal lengths. Many expert cinematographers have adapted quickly to this issue and have used it to their advantage. Because the target CCD is smaller, back focus is more critical on HD cameras. Make sure your 1st AC and operator know how to properly set the back focus or your images might be soft.
If you are using a light meter, it is generally accepted to rate HD cameras at 320 ASA for normal exposure. This rating can be changed in many ways including "pushing" HD by adjusting its sensitivity in the menu. This has some limitations, and "noise" can be introduced if pushed too far. HD is tungsten based. ND and color correction filters are built into the camera and are ND.6, ND1.2, ND1.8, and also an 85B+81B. If desired, rating HD stock at 400 or 500 ASA will help protect the highlights a bit more by naturally under exposing the image.
Highdef "exposes" like color reversal film. It has much more bottom end in the blacks than top end in the highlights. It's better to under expose than to over expose. Experts like Sean Fairburn call it 4.5 under and 1.5 over. That's the acceptable exposure range.
In addition, shutter speeds similar to film acquisition can be set. For 24P production, the electronic shutter set to ON @ 1/48th it is equal to a 180° shutter in film. Shutter OFF increases blur in motion equal to 24FPS @ 1/24th.
When you shoot 24 frames per second, it's usually best to actually shoot at "23.98P" not "24P." This difference was created to conform more easily with NTSC video and audio rates. If you shoot at hard 24P, you will have difficulty downconverting and keeping sound in sync.
It is good practice to record the master sound on the HD tape in addition to external recording devices (which should be running at 29.97 NDF). Shooting this way will save money by skipping timing and syncing of dailies. These steps are replaced with downconverting the field tapes to video.
Highdef Tape
Sony HDCam camcorders hold a maximum load of about 52 minutes in length shot at 24P. The same tape will only hold 40 minutes if shot at 60i. HDCam field tapes are available in 52 and 30 minute lengths (40 and 22 for 60 interlaced). Panasonic DVCPRoHD camcorders have a maximum load of 46 minutes.
Generally you don't load directly from your HD masters into your editing system for offline because deck rental is too expensive. You would instead downconvert your footage to DigiBeta, DVCam or other NTSC formats and offline conventionally.
One HDCam tape, 52 minutes long, is equal to 5,000 feet of 35mm film. The average cost of 1 52 minute HDCam tape is about $60.00. They come in cases of 10.
Crew Issues with Highdef
It is myth that you need less crew with HD. For the same quality in 35mm production, you need about the same number of personnel. Only the camera department has a change, losing the need of a loader, but gaining the need of a Digital Imaging Tech. The Digital Imaging Technician is like an engineer on the set who makes sure the camera is operating properly and handles the settings within the camera and all the monitoring equipment.
Lighting issues with Highdef
It is a myth that you need fewer lights with HD. The same number of instruments are needed whether shooting film or HD to create the same effect. Film can sometimes be shot with available light and so can HD. It should be noted that on sitcom lighting, it has been shown that smaller lighting instruments can be used with HD. For example a 1K might be substituted with a 500 watt instrument. The overall intensity of the light can be less, but the number of instruments stays the same.
Sometimes you need more light with Highdef. This occurs when you are outside and need to overcome bright back lighting. You will need more fill for faces in this situation because HD does not handle contrast as well as 35mm film, and you will have to pump up the light on the foreground object to keep the overall image within the latitude HD allows.
Before the Shoot
Sean Fairburn in his "HD Tips" column in Highdef Magazine says that the following questions should be answered before shooting begins. His answers are in italics.
- Where is the show going once done? TV, Feature, DVD, Internet, Interactive CD-ROM. Each one may requires different pathways in production.
- What frame rate will you shoot? 1080 is not an answer. 23.98Psf, 25Psf, 29.97Psf, or interlace 50i, 59.94i (see they're all 1080 on the Sony camera). I prefer the look of 23.98Psf.
- What aspect ratio will you compose for? HD is 16x9. Will you use 16x9 (1.78), 1.85, 4x3 edge cropped from 16x9, 16x9 letterboxed inside 4x3? For television we usually shoot for 4x3 but protect for 16x9, but 16x9 letterbox is becoming more widely accepted.
- What safe area will you use in the viewfinder and through post? 90%, 95%, 92.5%, 80% or a custom size? I use 90%.
- Will you record sound on the camera as it is shot and/or record separately? Sync sound as it's shot vs manually syncing sound in post ($$$) or both? I like to always record on the camera even when shooting double system.
- What time code method will you use: free run (time of day) or record run? Free run is broken code based on the time of day you start each take. Record run continues the same time code from the previous take at each new take. I always use record run and number my tapes hour 1, hour 2, etc.
- What is the route the footage will take through Post? For example: downconverts to Digibeta for Avid offline, then online in HD. I like to downconvert to DVCam to keep it digital, and hopefully convince the producers to not finish in
Digibeta.
- Will you complete the soundtrack before or after the online? In can be done either way, but it is safer to do your final mix after the online to make sure it's perfectly in sync with final picture. I recommend locking picture in online first.
- How do you intend to move the camera? Dolly, boom, ped, sticks, geared head, fluid head, SteadiCam, handheld? I use them all, so I prep the camera accordingly. Make sure your lens choices are appropriate for the way you intend to shoot.
- Are you shooting with primes and cinestyle zooms or ENG(electronic news gathering) style lenses? I shoot with them all. The ENG lenses are great for handheld shots.
- What accessories will you need? For example: Will the DP be watching the shoot on a monitor. What kind? How will you shield it from stray light? Consider all accessories and setup time for both.
- How much work do you expect to do in color correction? Getting as close as possible to the intended look when shooting will only help. But remember not to close out your options for change unless the look is cast in stone. I believe in doing as much as possible on the shoot. You never get enough time in color correction.
- How will you intend to monitor the HD in the field/on set? HD and/or downconverted images, and will there be video playback? Size and proper viewing environment must be considered. 9 inch for composition only, 24 inch true tech evaluation in dark. I like to use the 24 inch HD monitor on an HD Cart with a special HD Tent(www.filmtools.com). I Downconvert for video playback whenever possible. It's not a good idea to use the camera for playback.
- Are you going to hire a DIT(Digital Imaging Technician) or are you going to fly the plane? Getting an experienced technician will help insure success. I learned to fly, but I hire DIT's whenever possible.
Every show is different. This list is intended to open up the necessary dialog with those persons responsible for the successful production of the program or feature. Understanding the ramifications of each decision will help guide you to the decision that's right for you.
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