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Cut the Hype
Film is better than HD.
When it is in the camera yes. But after processing printing and telecine? The difference is much less. So much less that most people can't tell the difference between film and HD transferred to film. See judder for an explaination of what makes film look like film and how HD is being made to emulate it. Not necessary the best way to introduce different imaging and display technologies but a commercial necessity to slowly replace the recognised familiar look of film.
The surprise is, as demonstrated by the movie "Collateral" the audience is much less sensative to the video look than we have been lead to believe by the film community!
Which HD Format?
HDCAM? HDCAM SR? Uncompresssed DVCPROHD? HDVD? Don't test the numbers test the picture! Shoot tests of typical subject matter for your project, then transfer to film or view as intended for final distribution. Beware when comparing compression rates as frequently in-camera sampling rates are not taken into consideration.
Try and take the material through the post chin. Compression enginneers have doen extraodinary things, throwing away the data that our eye does not see so it looks good on a monitor, but is it robust enough to survive multiple passes, grading and large screen presnetation?
Which Camera?
Panasonic DVCHD Pro 3 x 1 million pixel chips, sampled at 10 bit recording onto DVCPROHD format 4:2:2 compression recording1280 x 720 pixels. Camera can be selected to 4fps to 60fps, recorder always records at 60p repeating frames if neccessary, extra frames removed in post.
Sony HDW 750 3 x 2.1 million pixel chips 10 bit A/D, recording 1440x1080 onto HDCAM format at either 25p or 50i
Sony HDW 730 same as 750 except it works at 30p and 60i only.
Sony HDW f900 3 x 2.1 million pixels, 12 Bit A/D recording 1440 x 1080 onto HDCAM format 3:1:1. Records 23.976, 24, 25, 29.97, 30, 50i, 59.97 and 60i.
It is possible to record a 1920x1080 4:2:2 picture from the above cameras into SRWI feild recorder D5 or hard disk recorders with a wide range of compression options.
HDV cameras. See my HDV primer
Other HD camera heads
Genisis12 million Pixel single CCD camera. Super 35mm format, uses 35mm lenses promoted to record onto SRW1, but will reocrd onto other formats.
The Viper camera system can output 1920x 1080 into any tape deck as well as disk recorders. The Venom is a dockable recorder to the Viper. It can also output 1920 x1080 in cinemascope aspect ratio.(the only camera to do this) This scope picture can also be recorded onto any HD tape or disk system. The Viper can also out put 1920x1080 at 444. In this mode the signal is recorded directly from the ccds without any in camera processing. A extra stop of latitude and greater control in post, at the expense of larger file sizes.
Sony HDC950 Can be configured for extra cost into a remote head package that is the smallest HD head at the moment.
Sony f950 outputs 4:4:4 and has slow shutter option
TV studio heads from Sony Ikegami and Thomson can also be used for HD acquisition by using a tape deck or disk drive.
HD for Theatrical release?
Anything shot in 24P or 25p can be scanned to film for theatrical release without any motion artifacts being introduced in the transfer itself.
Shooting at 25P in the UK is considered to be a good compromise for multi standard broadcast programs and also simplifies the post production route.
If the last movie you saw didn't have slo motion shots over 60fps then it could have been shot on HD! Seen Spy Kids II or Simone?
Resolution
In layman terms, there are 1920x 1080 pixels in the f900 camera. However these are sampled (or compressed) to 1440x1080 for the HDcam recording. Lucas films croped the center portion of the rectangle shaped picture (aspect ratio of 1:77) to project a anamorphic widescreen picture with an aspect ratio1:2.35. He ends up with a camera resolution of around just 800 lines from the original 1080.
Latest Star Wars uses SR recording so full 1920 x1080 pixels are recorded.
Interestingly an elaborate study undertaken by the ITU in 2001 concluded that perfectly exposed and processed 35mm film when projected in a good cinema has a resolution of just 600-750 lines.
Frame Rates
If you are in Europe continue to consider shooting 25p unless you have a good budget to pay for the limited amount of 24p kit in Europe. The frame rate that you decide to use will have a cost/hassle/availability tag attached in respect of your post kit. Everybody seems to want a VHS or beta or digi down convert of the project, from producers to post houses to distributors financiers ect ect. If you acquire at 25fps these a breeze to make in PAL countries.
The big issue with shooting 25p is that if the sound is also recorded on the camera there is no requirement to sync the rushes before viewing. An editor can begin work immediately on frame accurate in-sync rushes where the timecode is rock solid. He can use readily available PAL offline equipment. Sound dubbing and effects at the moment are readily available and cheaper in PAL format than 24p format as there is so much drama shot at 25p in Europe.
VHS or DVDs can be made where the timecode is burnt into the picture so even on a small screen a take can quickly and reliably found.
This has a knock on effect of altering the dominant form of scene identification to timecode rather than slate. Script /continuity need to record timecode information along with scene and take number. The timecode is relayed from the camera by radio link to a clipboard with a timecode display. This has been standard procedure for Television production for many years where the shooting ratio and total number of hours of material can be much higher than for a feature film.
On a recent HD feature we needed to view a background plate shot by another crew. It was difficult to find as we only had a scene and take number. We had to stop and look at a picture of the slate when all we needed to do was to fast forward to a timecode, had a note of timecode been taken by the scrit supervisor!
We know that the slate forms a important part of "steeling" the crew and artists for a take, but aren't the shouts of rolling! speed! and action! ample warning?
If your crew is new to video you may decide to pay the money and keep the clapper as a "comforter".
Of course there is no need to clap the slate as sound is and forever will be in synch with the picture. 4 tracks of sound if you use the HDSDI adapter on the camera.
For steadycam shots a radio link as guide audio track should be employed. A clapper board should be available for synching steadycam shots to the DAT.
In respect of steadycam, some crews are recording the sound from the DAT onto the HDcam after the take. This makes it easy for an offline editor to slide the DAT sound over the picture. For the budget conscious, this reduces the need for a DAT machine in the offline.
If you have a nice budget and have the resources to shoot and post produce in 24p sure, do it, for everyone else the money can be better spent. But probably one of the most significant savings on HD for low budget work is to shoot single system sound at 25p. See my producers guide for more information
I have yet to hear of a 24p long form project posted in Europe that did not have significant problems in post!
When is 24p not 24p?
When it is 23.98p. Very confusing if you are working with US partners or post. We think 24p is 24p but they tend to say 24p and mean 23.98p. One of the porblems with shoting 24p in Europe. Only neeeds one mistake in a audio or picture transfer and you are sunk.
Lighting HD
For the same depth of field for a given shot size you need much less light. (not necessarily less numbers of lights, just less light) Put another way you need less light to get the same depth of field as 35mm. For example its very useful in a night shot to maintain focus for a two shot of passenger and driver in a car. This is not achievable in 35mm without adding light to a level that begins to be brighter than low level ambiance of some street lights. Is lighting for HD faster?
Crew size
To achieve a similar result to 35mm the crew size needs to be similar. But, don't forget that the camera can record sound, that there is a remote head camera available and it is feasible to work quickly and reliably with a DP/operator and assistant under special circumstances. I would add that without a waveform or a monster size HD monitor that it is vital that the operator is very familiar with using zebras or has calibrated the sensitivity of the camera and uses a light meter to judge exposure. Although at low light levels a light meter is a difficult tool in comparison to a HD monitor.
Reliability
New video formats take time to settle in as do new cameras. Go to the cinealta f900 users reports for latest issues and faults with the f900!
However most HD kit does not work properly, this isn't a Sony issue. in fact the latest f900, f900H, after 3 years of bug fixes and further development is more reliable.
Costs
In 2001 a 40 minute HDCAM tape in the UK cost. £73
In early 2004 a 40 minute tape cost £43
In early 2005 it is £30 (runs to around 48 minutes at 25p)
A HD feature camera package of 2 f900 bodies, big monitor, 2 zoom lenses tripod, follow focus, mattbox will cost less than £30k a month to rent. For low budget work have the second unit make use of the camera on the first unit days off.
A cut down package of one f900, smaller monitor and 2 lenses can be rented for around £12k a month. These figures are based on 2004, when supply exceed demand.
Down converting
Most f500 playback machines machines in Europe have the PAL down convertor board. Check that they have the NTSC output with the 3:2 pull down board needed if you want to go from 24p or 23.98p to NTSC. The cheaper 25p, 50i M2000 HDCAM deck has downconveter will replay 24p but not record it.
Savings
For some projects with low shooting ratios the low cost of stock is not an issue. However directors will learn to use the low stock costs of shooting to their advantage.
Shouting "reset... still rolling" rather than "cut" after a unsuccessful take is an option that has a small cost penalty (compared to film). As Faye Dunnaway has observed directing on HD, this keeps the momentum of the scene alive and at the directors discretion keeps the tension of the actors "up" for the next take. It keeps the set quite and craft services from "diving in" and fine tuning makeup ect. or diving out to make a cellphone call. So it can help achieve a better performance and saves time. Another example, if the camera is left rolling for ten minutes during a sunset shot the director can also pull a time-lapse scene from it in the edit. He can choose the speed of the shot to fit the pace of his edit.
I was working on a HD feature with a director new to digital. I though that he was very prudent with his use of tape. He never said reset, although I continued to encourage him to do so. Even though we recded sound on camera he still wanted a clapper, to feel good. At the end of the movie I asked what he liked about HD. He said that it enabled him to do more takes. On a modest budget he said he would have to stop after a few takes if the performance was in the ball park. On HD he could push for a better performance. Not by shooting 10 extra takes but just one or two more.
In general, digital acquisition has cost benefits for producers and directors for some projects. But the benefits go beyond cost. "Live dailies" or near live HD bluescreen composting or instant replay of a steadycam shot in fine detail, or ending the day with a synched down convert including any audio playback, or on set editing,. No HD can not only save time it can give directors and producers confidence and encouragement to pursue different, risky or complicated creative approaches.
New directors are keen to embrace this new technology to get an edge by creating a new process of film making. Full of 24 inch monitor confidence the director is likely to be more demanding of the cinematographer. With over 90% of features being a commercial failure, perhaps the HD monitor will eliminate the blind faith that persists through the shooting period of rotten films. Savvy producers could easily make rough cuts of the daily down converts to see how the investment of the financiers is maturing. More to the point rather than showing financiers dailies a edited scene could be quickly assembled.
If a director and DP know what their post budget is then they can chose to use it for the following simple effects that can be setup and explored in an offline. The key to these effects is that the camera should be locked off or moving very little, some examples
remove a boom mike that has dipped into shot.Replacing signage. The script calls for "Hotel Hitchcock" very easy to put this into a wide shot of an existing Hotel if the Hotel sign has a border.
Creating signage. A neon sign can be easily created, in fact this was achieved in a Avid DS/HD in just ten minutes in a feature I shot.
For effect, adding a reflection into shinny surface like a floor.
Split screens are simple and fast to effect in a digital post environment. One can splitscreen the background action of take 5, next to the foreground action of take 1.
Digital acquisition
Cinematographers are in the difficult position of needing to extend their area of influence into post production and in the interim, into preproduction. This comes at a time where they also have to explore the technical characteristics of the new digital medium that challenges working practices and methods. Perhaps the most interesting change will be the relationship between cinematographer and director, where in some cases the authorship of the image may shift toward the director. The monitor allows directors and producers to have a closer relationship with the image on set than ever before. This is why some DPs do not want monitors on set. Go here to see why a monitor has an advantage over a light meter.
Bluescreen
You can key on HDCAM. Sure uncompressed recording is easier, but on projects I've shot so far the operators compare the keying to SDI. The important difference is that the composite is viewed on a large screen. Lucas has shot all of Star Wars from the f900 camera or its studio variant. Most was recorded on HDCAM in camera. The miniatures were recorded on a hard disk drive. This was faster and avoided the need for digitising tapes. This was achievable because the miniatures studio is linked to the compositing computers at ILM. The quality and resolution is also much better. But most of the keying that you see in Star wars is from HDcam.
A well shot blue or green screen can be keyed within minutes. However line producers should be aware that for large screen work the same amount of integration of foreground to background plates is required on digital as film. Adding reflections, and shadows for instance.
The SRW 1 tape recorder or hard disk recorders allow uncompressed recording or 4:2:2 recording. This improves keying,
Panavision
The Panavision f900 camera has superior lenses but they are not anamorphic. (A a anamorphic frame is "extracted" from the 16x9 frame) The resultant resolution, in theory anyway is derived from around 800 lines of pixels. The Panavision camera has a different body from the Sony camera and a different optical filter between lens and the ccds. The Panavised f900 encourages a traditional 35mm style of operation.
Anecdotal evidence suggests that back focus drift occurs more frequently with Panavision lenses which rumor has it Panavision are rectifying. Anecdotal evidence suggests that crews with little video background are not performing back focus adjustment correctly.
Fuji have made a series of Superzooms that on paper match Panavisons lenses. Although like the Panavision lenses to achieve a fast T stop they are very heavy with large front elements. The Fuji 12x superzoom is 200mm in diameter.
In Jan 2005 Panavision France have chosen 26 Canon lenses for their (non Panavised ) HD fleet.
Moco.
Some companies are saying that you can't shoot moco on HD. This is wrong! These companies know better! Don't be misled, seek advice from companies who have used HD. I have shot many scenes on HD with moco running at 25p and 30p. George Lucas has lots of moco moves run at 24p. It is much easier for a compositor to use HD digital material. No weave or varying grain to "tune out". My showreel has a 3 pass moco move that took just three minutes to composite in a online from a offline edl.
Not surprisingly there are many post houses who want to defend their investment of Spirits. Producers should be aware that the post houses that they may have been working with for years on film may not offer the most impartial advice in regard to HD.
Timecode
If running 25p you will get rock solid timecode down converts on your digibeta or Beta SP. These down converts can be edited on any PAL off-line.New
New Equipment
HD equipment seems to take around 2 years from date of launch to actually being available and working. Many models of HD kit , from NLE to recorders are not fully featured even after 2 years, with software upgrades promised that arrive years later.
Slow motion
There is a Panasonic slow motion camera that record 60fps at 720p, 10 bit processing and 1 million pixel imager. Sony recommend shooting at 60i for slo mo. The interlace frame does not produce a film like look without a de-interlace pass through a computer. In theory, de-interlacing reduces resolution by 50%, but in practice with Timewarp or other motion compensation software it appears less. Here is a deinterlaced 60i image
Thomson have a 60 p OB camera. Ikegami have a 120 fps camera that needs its own computer. Until a 1920x1080 120fps cmaera and recorder is introduced there will be compromises made shooting HD for slo mo. Sony have promised a full res 1920x1080 60p camera. Industrial cameras such as NAC and Photron have 1k resolution up to 3000 fps. Arri have packaged the NAC camera into the "Tornado".
Exposure
With a HD monitor or waveform or experience with zebras (in viewfinder not on the Serengeti) your exposure will be exactly where you want it. Don't think in terms of exposure latitude! Its a film concept that should be largely irrelevant on HD because you have a ringside seat at the image plane.
This ringside seat is the actual image that will be recorded, the number crunching of T stops, shutter speeds, gain are accounted for. There is an exquisite view of highlight detail (such as it is on HD!) and a enveloping view of shadow detail that is as precise as it is intriguing. Without the vagaries of film processing the DP need only apply his sense of the interaction of the form of distribution the feature will take.
If it is to be distributed via film the cinematographer and the director should have an idea of how a HD image, as viewed on a HD monitor differs from the same image recorded to 35mm film.
There is no excuse (or technical reason) for a poorly exposed shot on HD with a "35mm sized" crew.
There should be no excuse for finishing a days shooting with a take that the director thinks is technically ok, that isn't.
Sound department
From a producers point of view you are in a "bind". If you have a good budget simply stick to the established way of working. Sound recordists will be happy and not really bothered about what type of camera is on the dolly and you won't have any labour relation problems.
If you are on a tight budget you will start to question why you need separate sound. The clapper takes up valuable time and the energy of a member of crew who could be running for your coffee or looking after all those video cables. If you are clever you have probably figured out that you can go all the way to the online with the sound that has been recorded on the camera. What about steadycam shots? For this you do need separate sound. After the take, while the crew are wrapping record the sound onto the camera from the dat so the editor has everything on the same tape. I've yet to hear of any TV drama program in the UK that have been saved by the backup DAT tapes.
Clearly we are talking more about a labour issue than a technical issue.
The recordist will charge for and bring a DAT recorder to record atmospheres ect. What better way to record atmosphere tracks without the sound of crew wrapping than to use the camera? The camera can record 4 tracks of audio with the HDSDI adapter, DAT only two.
See the producers guide for more detailed information about sound. Video cameras are noisier than film cameras. They cannot have a barney as they will overheat.
Advice
Advice about HD is Conflicting. Post houses and film community are protecting their investment.You must assume obfuscation, lies and decete. Although this site is pro HD I have not left out important or relevent information or swept anything under the carpet. Remember this is the site with the list of faults of Sony's flagship HD camera.
The future
As Keynes said, the difficulty is not in learning something new it is in forgetting something that you already know. When embarking on a HD project, filmmakers need to reinterpret what they do, even the little things, as innovation comes with little ideas as well as big ones.
copyright Michael Brennan
