Digital Cinematography

In a nutshell "digital cinematography" is a term used to describe the process of using video to shoot something that either looks like it was shot on film or will be converted to film for theatrical release. It is not a reference to any particular format or standard, it is a style or technique that involves electronics instead of film.

Here I will be looking primarily at shooting techniques that can help reproduce the look of film. There are several issues such as choice of equipment, lighting, camera setup and post production.

There are many companies that produce a wide range of "digital cinematography" accessories for use with Sony HDCAM, XDCAM and Digibeta cameras. These accessories don’t actually change the way the pictures are recorded, they merely allow you to use film style accessories such as prime lenses and extension viewfinders. Many of these add-ons can in fact be used with many other video cameras.

So how does the use of a prime lens make the pictures more "filmic"? Well the answer is they don’t. What they do give is very high quality pictures due to the simpler optics required and force you to either move the camera or change lenses instead of just zooming in and out as you would with a more standard video lens. The fact that you have to move the camera to get a tighter shot gives a more realistic point of view than zooming in, after all our eyes don’t have zoom lenses. It also means that you have to think about the shot that little bit more and plan the shoot in more detail. Of course you can always treat a zoom lens like a prime lens, just use two or three fixed focal lengths and leave the zoom rocker alone.

One of the camera add-ons that really can make a difference is the use of a matte box and filters. Most video cameras use sophisticated (some more sophisticated than others!) electronics to make the image as detailed as possible, giving very high edge contrast. These "hard" edges are not something you normally associate with film. While you can turn down the amount of detail enhancement applied by most professional video cameras you do normally need some to maintain a reasonable looking picture. One way of softening the hard edges is by using a diffuser type filter such as a "pro-mist". Filters are a great way of altering the look of a picture; graduated filters can be used to reduce the brightness of a bright sky, bringing the contrast range to within the range the camera can handle. However they should be used with care, the aim is not to add some sort of psychedelic effect but to subtly enhance the overall image.

Without doubt the one thing that will alter the look of your final image more than anything is lighting. Most film shoots will make use of large soft light sources, not just a blonde or redhead on a stand. You can easily turn your blonde into a soft light by using some sort of diffuser, soft box or bouncing the light of a large white or reflective surface making sure its big enough and in the right place. Also keep an eye on the depth of field, a short depth of field tends to look more "filmic" as it mimics the way our eyes work, focusing on one subject at a time and not the whole scene. Also the film frames (16mm or 35mm) are larger than the 2/3 inch CCD imagers used in most broadcast cameras, this results in a much shorter depth of field.

Okay, so we’ve seen how lighting, filters and lenses etc. can be used to get a "filmic" look, but what about the cameras themselves. The real advantage that the current range of HDCAM and XDCAM HD cameras give you is the fact that you can adjust just about every setting and then store the settings on a memory card. Most modern cameras can be adjusted to some degree, the level of adjustment depending on the individual camera. For example the Sony DSR570 or DSR500 has a system of menus that can be used to alter many aspects of the camera’s set-up. It hasn’t got a memory card like the Digibeta's or some Panasonic models but instead has four built in memories. If you need to store any more settings than that then it’s simply a matter of writing the settings down.

Once the shoot is over there is still much that can be done to get that "filmic" look. Most films comprise mainly of sequences of shots that have been cut together, dissolves (mixes) are only used in a transition from one time or location to another. Again this comes back to the original planning of the shoot. If you’ve been careful at the shooting stage then there should be no need to use dissolves during most sequences. All too often dissolves are used to cover bad looking cuts. Careful grading (colour correction/matching) can be a help. Often the pictures will look more like film if the blacks are slightly crushed. Grading is especially useful if you can’t adjust the gamma settings on your camera, a good quality colour corrector will allow you to tweak the gamma of the picture, allowing you to match more closely the gamma of film stock.

Another technique used is the removal of one, or the doubling up of the two fields that make up each frame of the picture, after all film only has frames. This should be done with care as simply removing one field will halve the vertical resolution and may lead to some nasty jagged edges on near horizontal lines. A better method is to combine both fields into one new field that can be shown twice in each frame. In theory removing a field should make the pictures look poorer, but most people seem to prefer the slightly flickery look it gives.

Setups

Some Suggestions for setting up a DVW700 (and other cameras) to give a filmic look : (The suggested settings are for a generic average type film stock look and are for a DVW700WSP and assumes the camera to be in its factory preset state).

Master Black: Lowering the master black level will compress (crush) the darkest areas of the image. You will loose some of the detail in the dark areas but the image will appear to have a higher contrast range. Raising the black level will give a misty washed-out appearance. Suggested setting -5.

Master Gamma: Reducing the master gamma will make mid tones appear darker again making the image look more contrasty, use with caution if also reducing the master black level. Suggested setting Master Gamma -20.

Detail Correction: Reduce the amount of detail correction. This will soften the pictures slightly and reduce the black edge that can sometimes appear around the edges of high contrast images. If you are using some sort of diffusion such as a promist don't lower the detail correction too much Suggested setting -50 (Note you could take this all the way down to -99 but if you are using any sort of diffuser I would not go below -60).

Detail Frequency: Raising the frequency of the detail correction will boost the amount of fine detail in the image, however the image may actually appear softer even though it contains more detail. Suggested settings H dtl freq 3, V Dtl Black Clip 15, Dtl White Clip 11, Dtl Black Clip 5,

Crispening: Alters the apparent resolution through high frequency boosting. Raising the crispening level gives an apparent increase in picture detail, useful when the detail correction has been reduced. Suggested setting: Crispening 15.

Knee: Sets the point at which the cameras electronics start to compensate (compress) image highlights that threaten to overexpose or bleach out. Suggested setting Knee Aperture -3, Aperture level -2.

R Flare 50, G Flare 50, B Flare 50

Matrix: The matrix adjusts the way the Red, Green and Blue elements of the picture are handled and mixed together to create a full Colour picture. Adjusting the matrix settings will adjust the amounts of each colour sampled. It will NOT adjust however the white balance of the camera. The matrix can be used to "tint" the overall image. Suggested setting: Matrix Table A, Matrix R-G -39, R-B -24, G-R 6, G-B -41, B-R -15, B-G -4.

Depth of Field: Use as much ND as you can aiming for an aperture setting of f4. In some situations it may help to use a master gain setting of -3db however there is a very slight trade of in highlight handling.

Exposure: Under expose by half a stop or so.

These are my views on the subject of "Digital Cinematography".

Alister Chapman, Lighting Cameraman