- Analog and digital.
- Aspect ratio = width in relation to height (w:h)
- For film the aspect ratio is usually expressed with the height as unity: 1.37:1
- For digital it is a simple ratio with whole numbers: 4:3 or 16:9 (widescreen)
FILM
The analog version. Shooting on film is expensive, considering digital is more or less free now. However this is perhaps to its advantage in that you will consider everything before you press the record button – you learn skills and techniques quickly and in depth.
This is the moving image version of analog. You are recording light as it enters the camera rather than a digital representation thereof. Film actually records far better quality information than HD. However, the speed at which you can capture and play back the information, and the quality of playback, is limited by the capability of the recording medium and equipment. These are the basics: you choose a stock and shoot your film. You take it to a lab to be developed. They give you a rush print. You edit this – literally by cutting it up and taping bits together.
Now called a cutting copy, you take this back to the lab/ to a neg-cutter who will cement splice your negative, guided by your cutting copy, into an A&B roll – this is then taken to the printer to make a print.
GAUGE: is the width of the film. The most common are: Super 8, 16mm, 35mm, 65mm. A lot of artists use 16mm, so we have concentrated on that here.
16mm can be shot as Standard 16 or Super 16 depending on the camera used.
Standard 16mm
Picture area: 10.26mm x 7.49mm. Aspect ratio: 1.37:1 (very close to 4:3, TV) Double-perf: perforations on both sides – usually for high speed cameras. Single-perf: perforations on one side and soundtrack strip (magnetic strip for analog recording) on the other.
Super 16mm
Picture area: 7.41mm x 12.52mm Aspect ratio: 1.67:1 (very close to 16:9, widescreen, HDTV) Wider because it takes up the space used for the soundtrack, so you have to use single-perf film. If you want to project it as film with sound then it needs to be enlarged to 35mm, or the sound has to be played on another device.
You can shoot film in widescreen or extra widescreen using an Anamorphic or ‘squeeze’ lens. There are several different types of lens which give you different widescreen formats. It literally squeezes the image during capture. A similar lens is needed on the projector to expand or un-squeeze the image during projection. Super 16mm can extend to extra widescreen (CinemaScope) – up to 2.35:1
Film gives you a physical sense of duration: measurements of film = time. Oliver Bancroft
Film Stock
Companies that produce film stock: Kodak; Orwo; Agfa Fuji closed the film department at the end of 2012, but you can still get stock here: www.filmstockclearance.com
List of questions to consider when choosing stock:
- Do you want to develop the film yourself?
- Black and White or colour?
- What are the light conditions you will be filming with? New film stock will last longer if you freeze it straight away – thaw in a plastic bag so that condensation forms on the bag not the film.
Negative and Reversal
Negative film is just like a photo negative and is all in reverse so it has to be printed on another film stock for projecting. It is available in a wider range of speeds and colour balances, and has wide exposure latitude. Reversal film records a positive image directly on the film. It is usually associated with very bright and strong colours so you need to decide if you want this look. It is less expensive, has a higher contrast than negative, and preserves better. However it has a very narrow exposure latitude. Making film prints from a reversal film is a little more complicated than doing so with negative film.
EI: (Exposure Index). This is basically the speed of the film and you choose the film depending on what light you are shooting in. You choose this by ASA/ISO numbers. The higher the number, the more sensitive the film is to light, but also the more grainy the film image.
COLOUR: colour balance in stock has two main categories: daylight (D) and tungsten (T) – which represent what type of light you are shooting with.
Ektachrome 7240 stock is really grainy and good for getting that nostalgic look, but remember you will lose detail. Graininess is always more obvious in shadowy or underexposed areas. Kodachrome colour film is reliable even when long out of date.
Developing
- Most labs only develop and digitise (Telecine/TK).
- You can develop your own films – just like still photography. Make sure to choose the right film stock – it’s mostly a question of chemicals available.
Printing
- Some labs will develop your negative and give you a print.
- You can ask the printer to print the image in a certain way to give a certain look – e.g. sepia, changing colour ratios, contrast, colour balances.
- You can have your film printed on acetate or polyester based film stock: You can tell the difference really easily: you can tear acetate film.
Acetate is brittle, heats up quickly and damages and tears easily. It is alright if you are doing a screening, but most often artists’ films are in more or less constant use in the gallery setting. Acetate film can be alright if you have a very long looper thus giving the film time to cool down, but you will need to use a specific projector for it. Never use plastic leader with acetate film as it shrinks at a different rate. Polyester is more expensive, but is much better for use by artists. Polyester is stronger and tougher and so wears better than acetate. Its storage life is up to ten times longer because it is far more chemically stable.
Editing on film
- The great joy of using film is to edit the film itself with a blade and tape!
- The numbers down the side of the film are called Key Numbers and are really useful for finding frames. 16mm has a key number every 20 frames (most common) or 40 frames in some film stock. If you want to edit as film with a cutting copy, be sure to ask for the key numbers to be printed.
- For complicated/longer films, a Steenbeck
Editing
Table will prove essential. You get courses and workshops to learn to use them. One of the great things about them is that sound and image are kept separate so you can synchronise them. To edit film with sound on a Steenbeck, you will need your sound on SEP Magstock. Further reading: Cherry Kinoe Wondermental… http://en.pleintekst.nl/cherry_kino.pdf
Splicing
This is cutting the film and then joining it together to make loops or edits.
Tape
- The quickest way to splice film together and also the easiest to remedy. Unless you are making a simple loop, tape splicing is really for editing your cutting copy.
- Each film gauge has its own size splicer. CIR splicers are a good solid make. Be sure that the blades are sharp, push the guillotine arm toward the film and cut quickly for best results.
- Many splicers will have a metal knob on the side – this very gently moves the teeth, pushing the film together/apart for a perfect join.
- Don’t be afraid to stick the tape down properly to the film. It needs good contact.
- The splice must be taped on both sides of the film. After doing both sides it is always worth turning the film over one more time and cutting the tape – this makes sure the edges are smooth and sprocket holes cut cleanly.
Cement
This is for neg stock, not film stock (you cannot splice polyester film this way); the process is complicated and normally used for cutting and editing your negative – it’s the most affordable and most durable, but you need someone to teach you.
Cameras
- Because basic film formats have remained the same, you can still use old cameras – they just need to be working properly.
- When considering what camera to use – if you are having sync sound then you want a camera with a crystal sync motor.
- For a sync camera, Arriflex, Ecclair and Aaton are reliable makes.
- A Bolex camera is a great non-sync 16mm camera. It can do stop frame animation as well as a variety of film speeds and it is wind-up – no batteries needed.
See: Andrew Alden http://bolex.co.uk/andrew/Bolex_Site/BolexHome.html
DIGITAL/VIDEO
- Carry spare batteries and memory cards!
Memory cards
- SDSC (Secure Digital Standard Capacity): up to 2GB
- SDHC (SD High Capacity): between 4GB and 32GB.
- SDXC (SD Extreme Capacity): between 32GB and 2TB
- CF (Compact Flash): more professional use, 2TB and above; different speeds:CF, CF High Speed, CF 3.0, CF 4.0.
Choosing a camera
- Go online and read the reviews!
- Think about your end result – the one you want most often, and work backward.
- Camcorders are designed for continuous shooting. DSLRs are not.
- Camcorders look ‘video’; DSLRs look ‘film’.
- DSLRs are inferior for recording sound, but there are ways around this.
- Zoom: if you want to zoom lots, go for camcorder.
- Resolution: are you going full HD? You want 1080p.
- It’s worth remembering, if choosing your camera for video and looking at megapixels – what are you going to play your video on? The highest resolution players we currently have are 1080p = 2.1 megapixels. 4K is coming but that’s still only around 8.5 megapixels. There is no point in investing in mega megapixels over other features when, for now, the quality is just going to be lost on playing.
- When choosing a camera, make sure it has a separate audio input – most should have a mic jack. The pricier ones have more professional XLR inputs.
- HDSLR: is a DSLR camera with the capability for HD recording.
Filming
- Keep a checklist of equipment throughout a shoot.
- For panning shots, pull your tripod handle gently with a rubber band – elastic absorbs movement making it look smoother.
- Experiment and see what is possible.
- www.vimeo.com/videoschool
Sound
- DSLRs record sound, but it’s not great, so plug in a mic and/or use a portable audio recorder.
- DSLRs don’t have XLR inputs, but you can use XLR adaptors.
- Double-check power requirements: XLR microphones normally power off the camera; microphones for a mini jack usually need batteries – have spares.
- Make sure your microphone is on and the camera set for it. Older cameras won’t detect an external mic automatically. You have to go into settings and select.
- Do a sound test before you start recording and listen to the playback.
- If you go for a wireless mic, make sure its receiver fits into your audio input.
- Professionals tend to use portable audio recording devices for the best sound quality – go with the kind of sound you want: digital recorder, dictaphones, DAT, minidisk, tape, your phone. Experiment with sound, but read online reviews about devices before you buy. To sync sound when editing: clap your hands or tap something loudly on camera for a sync mark.
Editing
- Remember that all computers have free editing programs built in: Mac: iMovie; Windows: Windows Live Movie Maker. These are actually pretty sophisticated; you don’t have to invest in the more expensive programs until there is something you need that one of these can’t do. Most programs run along the same lines. It all just takes some time to get used to the frills. The 4 step guide:
1. Put your files in the Bin (it’s really called this). 2. Arrange them in time (on the timeline) – you can trim them down and move them around while doing this. 3. Get your audio onto the timeline – look for a special button (something like sound and music), trim and arrange as above. 4. Export. Ok yes, it’s a lot more complicated, but when you have mastered the basics there are tutorials on your software, helpful videos, and a million experts on the net.
- You cannot upgrade quality in editing: eg. if your camera records at a certain resolution, you can select to make it higher, but your file still only has the information the camera recorded – you will not be increasing your quality, just increasing your file size.
Compression & coding/decompression & decoding
Compressing and decompressing, and the ways to do it, is seriously technical stuff, but we have tried to include the basics that you will need to think about for making and showing video. The less encoding you do, the bigger your files will be. There will be more detail in the video and audio files, but remember that the quality/detail has to be there in the first place. Don’t over-spec the containers and codecs for lower quality recordings: eg. if your camera records 24 frames per second, there is no point in encoding it at 60. Match your specs with your recording device and save a few versions at different formats and qualities.
Make your master the highest res possible for what your camera/audio recorder can achieve, and then export different formats depending on where they are being shown: cinema, DVD, Blu-ray, various media players, online. Be prepared to compromise depending on your media player (that you have now/will have in the future).
Resolution
Resolution
is basically how many pixels an image contains. It is typically expressed as: image width (in pixels) x height (also in pixels).
You usually want to match the resolution of your camera. Common (current) resolutions: SD (standard definition): 640 x 480 HD (high definition): 1280 x 720 Full HD: 1920 x 1080 As a shortcut, sometimes people just refer to the height (480/720/1080) Get ready – Ultra HD is coming: 4K: 3840 x 2160 pixels or 4096 x 2160 pixels. 4K is four times the high definition resolution of 1080p.
For resolution to be displayed it also involves scanning: ‘p’ : progressive ‘i’ : interlaced Progressive scan is twice as fast as interlaced. The difference between 720p and 1080i is minimal. 1080p – is the topmost quality we can do at the moment.
Frame rate
Video is usually produced and shown at between 24 and 60 frames per second – ‘the frame rate’ – written as fps. You usually want to match the frame rate of your camera. You can export with a variable frame rate, but this can cause problems; play it safe, stick with a constant frame rate. Shorthand: 1080p/60 = “resolution of 1920 x 1080; progressive scan; 60 frames per second.”
Bitrate
Bitrate
is the amount of data that is used for each second of video, generally measured in kilobits per second (kbps). If the bitrate is too high, your file will just be too big without any real increase in quality. If too low, you lose detail and start to see those hazy blocks. Some media players specify the maximum bitrate they can play. CBR (constant bitrate): uses the same amount of data every second. VBR (variable bitrate): adjusts the amount of data used depending on changes between frames. Quality between CBR and VBR varies, to begin with just try your video in each and see which is better.
Video Formats
Video formats involve codecs and containers, although people also call containers formats or file formats. For the purposes of thinking about it for delivering your film, think of a codec as compressing/coding and decompressing/decoding the video and audio files you have edited. It compresses them up into smaller bundles and puts them into a ‘container’ so you can carry them around and store them easily. When you want to show your film, it takes them out of the container and decompresses them so they look nice.
Codecs
There are two main types of codec you will need to think about:
Intra-frame codecs – use these for editing – record and store all of the information about every single frame – examples: Uncompressed (but very big file sizes); ProRes; DV; M-JPEG; X264 lossless Inter-frame codecs – use these for delivery – from frame to frame, sometimes very little changes (for example a background may change very little in each split of the second, or just one part of the frame will be in motion), so the computer just records the changes instead of all the information about the still. To determine the amount of change, a computer uses a codec – examples: XviD, DivX, 3iVX; MPEG-2; MPEG-4 / H.264; WMV; RealVideo; VP6, VP7, VP8
- You have three main things to choose: a video codec; an audio codec; and a container to put these two into. The three have to match each other, and they have to match the media player you will be using at the other end. Decent audio codecs: AAC, MP3. Good video codecs: H.264 (also called MPEG-4 part 10 or AVC), MPEG-2.
- For video: H.264 is currently the most widely supported, the most versatile and you can adjust the size depending on what you are doing with your video. H.264 also gives you a higher bitrate for your file size.
- For Blu-ray you can also use H.264.
- For Audio: AAC is currently the most supported.
- If you need a particular codec, download it from the internet – always best to go to the manufacturer’s website. Remember codecs have to match your operating system.
- If you have sound but no image, it is often a codec problem.
- Get ready – High Efficiency Video Coding (HEVC) is coming. It should double the compression ratio of H.264 while providing the same or better quality, and it will support Ultra High Definition.
Containers
These ‘contain’ the files for you once the codecs are finished with them. Most good containers can hold a variety of codecs. Container formats related to Mac and Windows: Quicktime (MOV) – Mac AVI – Windows Other containers: MP4, FLV, ASF, MKV, VOB, OGG Containers are identified by filename extensions, i.e. the .xxx after the name of your file. For example:
Extension Filename / Container Format .mov / Quicktime .avi / AVI .mp4 / MPEG-4 .mkv / Matroska .rm/.rmvb / RealMedia
- MP4 containers are the most widely supported.
- H.264 and AAC in MP4 will give you good quality, decent file size, and play on almost anything.
- MPEG is slightly annoying because there are containers and codecs named this (but they are different things).
- Best not to use H.264 with AVI containers.
- If playing off a laptop, I always use VLC – it has the most codecs on board and can be used on Mac or Windows.
- I struggle most with codecs when playing off a media player. You really have to check the individual media player to see what formats and codecs it will support (these also might be limited in resolution and fps). Check all these, then deliver your file accordingly.
- For Brightsign media players (got to love them!) deliver your file like this: Quicktime .mov container; H.264; AAC; at 25,000 bitrate. If you use the MPEG transport stream as the container, you can take this up to 35,000 bitrate (.ts) Various calculations online: www.hdslr-cinema.com/tools Freeware: Video Spec – this is great, you can analyse any video. Use
Bitrate
Pro as a calculator for bitrate variables: http://videospec.free.fr/english/