Digital video: Background and purchasing decisions

This page was written by Christopher Spry and last updated on 11 June 2002.  It discusses the options I considered before selecting the digital video camera, computer hardware and software that I would use to make digital video films.  Please let me know about errors or omissions.

I am an amateur photographer with several years experience of analogue video. About three years ago I began to find out how to create digital video movies and still pictures. I wanted to be able to edit digital video on a personal computer, then store and output digital video film to either television, printed medium, CD-ROM or web servers.  While searching for suitable information, I came across many useful web pages of information and advice on these complex and rapidly-moving topics. If you have similar interests, you may find some of the information and links useful. Note that my brief survey has not included non-PC computing hardware platforms, such as Apple and SGI computers, which are covered extensively on other sites. The camera equipment, PC computer hardware and editing software that I finally put together in January 2001 are listed below. See also my second video page on 'Digital video: Editing'. 

Index:

1. Background information:

A few years ago, video camera only recorded in analogue video formats. Now, analogue formats are being replaced by digital video formats. Digital video is usually recorded into 'avi', MJPEG', QuickTime and other types of digital video format, so that it can be stored on computers, sent over the Internet or viewed directly on computer monitors or TV sets. Another major benefit of digital video is that it can be edited on computers and copied repeatedly without loss of picture or sound quality. However, until digital television and digital computer monitors become more generally available, analogue devices (usually a standard TV with or without a VCR) will generally still be used to view digital video. But this creates problems, as there are several different analogue TV video formats, including NTSC and PAL, to be considered. In addition, TVs and computer monitors differ in the way that they present video (gamma values), so digital video that looks right on one type of display, may appear wrong on another.

Hopefully, the day will come when all images are recorded, edited, stored and played back in standard digital formats and when all display devices use a common digital display standard. Until then, there are selections and compromises to be made because of differences in current video and graphic 'formats'.

Currently, camera equipment,  computer capture devices and software are available to
(a) make digital video (DV) movies or clips, using near-broadcast quality DV camcorders
(b) transfer the videos to PCs using DV capture cards and
(c) edit video with non-linear editing software (NLE) so that the video can be (1) output to disk, tape or CD-ROM with no loss of sound or video quality from the original recording (2) copied to VHS video tapes for viewing with VCRs and standard TV sets.

There are two principal analogue transmission video formats in use around the world today:

'DV' can be shown directly on digital television or digital video screens. 'DV' has to be converted into analogue streams for showing on analogue televisions, when it may be in either (a) the 'NTSC' standard, when it is given a timebase' of 29.97 frames per second, 'resolution' of 720 x 480 and 'sampling' of 4:1:1 or (b) the 'PAL' standard, when it is given a 'timebase' of 25 frames per second, 'resolution' of 720 x 576 and 'sampling' of 4:2:0. Fortunately, consumers need not be concerned about these technical details, unless they stray into the world of professional digital videography. 

In addition to differences in the format of the video that they receive, TV screens and computer displays also have different gamma values. This is the relationship between numerical pixel value and the amount of light displayed. Video cameras usually have no way to compensate for this difference, to allow the user to select for one or the other. The only way to do this is to set a 'gamma correction' or to alter the 'brighten/contrast' in the computer's video editing software. Of course, if you do this and then send the image back to your camera as a title screen etc., it will now look too bright on a TV screen and vice versa.  You can try to adjust the computer monitor to match the TV appearance, which helps somewhat.  This issue is discussed in the Beale FAQ. An ideal option, if the output will go finally to TV, is to use a 'true broadcast specification' monitor, rather than a standard computer display, for viewing and editing the video before it is stored for playback. High quality video is also checked with 'Vector scope' and 'Waveform' monitors. These have a setting with 'colour bars' to define the standard output and enable edited to be saved in an optical form.

Converting PAL and NTSC VCRs are available that produce a 'true' conversion of one format to another and the converted signal can be saved to tape. Some cheaper VCRs can output NTSC tapes to a TV in PAL format, but this can not be captured as PAL video because they only create a 525 line\60Hz picture with a PAL type colour subcarrier. Also, note that if you  convert from PAL to NTSC the video can ' stutter' due to the extra frames per second. Converting video from NTSC to PAL requires either stretching the frames and the reducing picture quality or adding black bars to the top and bottom of the picture. For these reasons, it is desirable to record to the format they will be output. Canopus sell software called 'DV Format Converter' for about US$400, to convert digital video recorded in NTSC to PAL or the reverse. Keene in the UK, also sell hardware to convert between the two standards. Often is it best to have the conversion done professionally for small numbers of tapes.

Here are some links with background information on digital video:

2. DV camcorders

Categories

DV cameras can be grouped into three categories:

Traditional analogue camcorders cost between £300 and £1,000.

Comparisons

'What Camcorder' magazine has awarded the Sony TRV30 the 'Camcorder of the Year' award in their January 2002 issue. The magazine says 'It managed to pull off the difficult balancing act of being a well built, robust machine that was both compact and stylish ... video was simply beautiful. Images revealed themselves to be sharp and well detailed, with good colour reproduction and very little noise ... Put quite simply, you'll be hard pushed to find a more versatile tool with such functionality'. When launched, the TRV30 cost about £1,500 in the UK, but now it can be found with full warranty for less than £1,000. Other 'What Camcorder' awards were:

Comparisons of several DV camcorders are made in the 'DV Magazine' review of DV camcorders. The Sony 'DCR-VX1000' (see Pete Skirrow's review),  'DCR-PD100', 'DCR-TRV900' and the Canon 'XL1' all earned high scores. Their image quality was judged to be almost as good as the Sony 'DSR-130', which is a broadcast-quality DVCAM unit with 510 lines of resolution. The Sony 'DCR-PD100' lines of resolution were 470.

Ten 'entry-level' cameras were reviewed by 'PC Magazine' in the 6 April 1999 issue, using the Canon XL1 for comparisons. The Editors' Choice was the Sony DCR-TRV900.  The Panasonic NV-MX300B was was reviewed in February 2001.

David Ruether has information on current (December 2001) Sony mini-DV cameras, comparing them on the basis of their CCD chips. He has also compared the following cameras and provided 'frame-grabbed'-pictures to compare them: Sony PD-150, PC-1, TRV-9, TRV-900, VX-1000 and VX-2000; Panasonic AG-EZ30U; and Canon GL-1 and XL-1 - with a Sony UVW-100 Beta SP with Canon YH1 8x6.7 lens used as a reference. Comments about the Sony PC-7 and the Panasonic AG-EZ1U are also included there.

ZDNET has reviewed and compared eight MiniDV cameras costing £650-£1,500, on 10 March 2000. The JVC 'GR-DVL9800' was the 'Editor's pick' @ £1,300. 

'PC World.com' has reviewed in June 2001 Canon's Elura 2, JVC's GR-DVM90, Sony's DCR-PC110 and Panasonic's PV-DV401

'SimplyDV.com' has reviews on eight MiniDV cameras: Sony DCR-TRV20E, Sony DCR-PC110E, Sharp VL-PD6, JVC GR-DVL9800, Canon XM1, Sony DCR-VX2000E and JVC GR-DVX10 DV camcorders and the Sony DCR-TR620E Digital8 camcorder. The reviews are based on articles that were published in the U.K. 'Camcorder User' magazine in the year up to January 2001. It also has advice on choosing and using digital video cameras, devices and software.

Personal reviews of many camcorders are available at 'Camcorderinfo'. 

Selected cameras

Necessary features are IEEE-1394 for DV input and output and three 'charge-coupled device' (CCD) chips for optimal results. The following are highly regarded:

Enabling DV camcorders in Europe with 'DV-in' disabled

The EU requires DV camcorders to be sold with 'DV in' disabled unless they are also classed and pay additional tax as 'videoplayers'.  Several web sites have methods to activate 'DV in', when it has been disabled on models sold in Europe, see (1) Datavision, (2) DV 2000 and (3) Smart DV, UK, £40 for Panasonic DV camcorders. Steve Savva discovered the Panasonic 'dv-in' source codes and writes that his software is the cheapest option!

Cleaning video camera heads and moving parts

Do not clean the camera's head, unless you regularly see video 'drop outs' in video made with the camera. First, try using a (dry) head cleaning tape sold by the camera manufacturer for this purpose. If this does not solve the problem, do not attempt to clean it manually yourself. Never touch the recording head with any cleaning device, unless you have been trained how to use it. Instead, take the camera for cleaning by a skilled professional video technician, who will not use 'cleaning buds', 'q-tips' or any material other than chamois leather or lintless swabs, which are sold specifically for 'head' cleaning, and highly purified specialist cleaning fluids. Most samples of cleaning fluid sold to the general public will damage a video camera by leaving a film that will fuse to the recording surface. Stroking the head across its surface can ruin it. Movement must be along the direction of the tape. You have been warned!

3. Video tapes

4. Surveillance video cameras

See Nevada Systems Inc. and Supercircuits amongst others.

5. DV camcorders and still pictures

There is an extensive comparison of still pictures made with many different video cameras by a_haru@big.or.jp. The text is in Japanese. To view a translation of the the text and to see the pictures, connect to BabelFish, enter http://www4.big.or.jp/~a_haru/index.html into the 'Website' box and select the Japanese to English translation of the web page. Video cameras can not yet match the picture quality of dedicated still cameras, when the image contains more than about 0.4 million pixels.

The Sony DCR-TRV900 gives good quality still pictures up to the resolution of the camera, which is 720 x 480 (345,600 pixels) for NTSC and 720 x 576 (414,720 pixels) for PAL You can record stills directly to a compact flash (CF) card, floppy disk or a Sony memory stick. Stills of equal quality can also be taken from the video using many non-linear editing programs, such as DVStorm.

6. Microphones and sound recording equipment

There is a review of microphones at Audio-technica. Good video cameras usually have competent on-board microphones. For amateurs, the Sennheiser MKE-300 short-shotgun microphone is an effective and inexpensive microphone to use in the hot-shoe. It can be bought £130 or with the matching 'Rycote windgag' for £140.00. When wrapped closely in air conditioner filter foam, this microphone is said to be resistant to wind-noise. 

For 'serious' audio, put the microphone close to the sound source. This requires a wired microphone and cable, or a wireless microphone. The Azden WLX-PRO wireless microphone tie-clip omni-directional microphone with discreet pocket transmitter and camera mounted receiver costs £179.99.  Most videographers have several microphones for different situations and an even larger assortment of cables and adapters. Jay Rose has advice about professional audio for broadcast and multimedia. 

The Azden Pro Series VHF Wireless Lavaliere Microphone System (search here), which costs about US$250.00, provides a wireless lapel microphone with transmitter and a receiver that fits on or under the video camera. Alternative microphones for professionals include the Sennheiser ME-66 microphone and K6 power supply, which records speech particularly well. There are other suggestions. These can be 'Shotgun' microphones, which are highly directional and have a long barrel that is pointed at a distant source of sound. An excellent shotgun microphone for the Sony TRV900 is the Sennheiser MKE-300 microphone which costs US$200 and uses one hearing aid type battery. It has a built in coiled cord that terminates in a stereo mini-connector.  If your camera takes a stereo mini-in, you will need an 'XLR to stereo mini adapter'. Alternatively, you could buy an XLR box for your camera such as the 'XLR Pro' from Studio One, which costs about US$219. The Beyer MCE86s microphone is battery powered and works well with video recorders. You can purchase from Robert C. Fisher at rcfish@pacbell.net, a device that prevents recording of head/transport noise from a Sennheiser microphone mounted on a TRV-900. There is a radio-link microphone system from Samsontech.

Wireless microphones: Several cameramen have posted Usenet messages that Lectrosonic VHF 185 or 187 wireless systems are excellent devices and often can be bought used.

Audio is usually monitored, as it is recorded, using headphones attached to the camera. If this is not possible, there is a device which fits on the camera's accessory shoe called 'VU-PRO' (rather expensive at US$219), which gives a visual indication of the strength of the sound signal being recorded.

7. Filters & lenses

8. Lights and lighting

The Hahnel 'Zoom Opto 35' 6 volt on-camera lighting system is recommended and costs about £100. For independent digital cinema, industrial work, or training videos, more lights will generally be required. Lighting at Lowel is reasonably priced. Professional lighting equipment is available from Dedolight, Mole-Richardson, and Arrilights.

9. Tripods, trolleys, booms etc.

There is advice on how to reduce 'camcorder shake' while filming, using a variety of techniques. 

10. DV capture cards and devices with editing (NLE) software

Some computers have IEEE-1394 connections built in and a range of video (NLE) editing software can be bought separately to work with them. The IEEE-1394 specification is called 'Firewire' by Apple and 'i-Lnk' by Sony, which can be confusing, as they are identical. Most computers will require a capture card, to provide a way to send the video from a camcorder to the computer. All digital video capture cards should have one or more IEEE-1394 connections, so that video and sound on the camera can be sent to the computer (and usually back again) without loss. DV capture cards usually also have analogue connections for s-Video and sound. Some cards have a 'breakout box' (set of connectors) which can simplify cable connections. Some of the more recent cards have their connectors routed from the back of the capture card, through the computer to a panel set into the front of the computer. This makes it easier to attach the camera and reduces 'cable-clutter'.

Many DV capture cards are bundled with editing software that has been configured to work with them. Purchasing decisions should be based on both the quality and cost of the card, and their bundled NLE editing software. The cards listed below all have software included for capturing video from a camera, editing it and sending the resulting video to a VCR or camera.

There are reviews of IEEE-1394 input and output (I.O.) cards by 'Electronic Mailbox'. Pat Leong had provided a feature compilation of IEEE-1394 cards. The 'Silver List' of cards is maintained by Richard Lawler. Open System DV & IEEE-1394 non-linear editing  for PCs. There are also some IEEE-1394 PCMCIA cards for notebook computers. The following list contains the most popular retail DV capture cards, which are not listed in any particular order.

There is a review and comparison by David Em of three add-in boards for PCs that provide real-time DV editing and playback: Pinnacle Systems' 'DV 500 Plus', Matrox 'RT2000' and Canopus' 'DV Storm'. 'PC Magazine', in February 2001, has reviewed a number of the cheaper analogue and digital video capture hardware devices and video editing software, with usability tests. It pointed out many of the problems that are still present in video capture and editing.

11. IEEE-1394 PC connection cards without editing (NLE) software

The IEEE-1394 ('i-Link' or  'Firewire') connections are used to transfer video and audio streams between a video camera and a computer. They also enable camcorder control signals. Normally, they are not bundled with DV editing software. There are many of these, see for example:

12. Analogue/digital conversion

Many people who have analogue tapes and want to convert them to digital formats. There are several ways to do this. The easiest is to purchase hardware designed to do this, such as Canopus 'ADVC-100', Dazzle's 'Hollywood DV Bridge' and 'Director's Cut'. Dazzle have a support web board with information about problems and possible solutions. (Some Dazzle units have had to be returned as unusable). Bidirectional 'Digital to Analogue Converters' (DACs) are available from Keene. The Sony 'Digital Video Media Converter' DVMC-DA2 costs slightly more and has connectors that allow conversion in either direction and to IEEE-1394. It can "convert Analog Video to Digital Video, or Digital Video to Analog; Transfer and Store Analog Video into the Digital Domain; Makes any TV i.LINK Interface Compatible; Selectable Switch for Analog or Digital inputs; Digital Audio Transfer". See a description. It appears to be the unit of choice for conversion work. Check that the chosen devices support PAL, if you need it. Note that, most modern DV camcorders can convert to and from analogue formats and there are many modern VCRs that do the same, but are probably not worth buying to do just conversion work. SwiftDVD.com in Atlanta, Georgia, USA provide a service to convert home videos and VHS/VHS-C including Mini DV, Digital8, 8mm Hi8 (Super8),and VHS/VHS-C (including VHS, S-VHS, VHS-C and DVHS) to DVD.

13. Video compression

Uncompressed source digital video takes up large amounts of storage space. There are many ways to 'compress' video, to take up less space but still provide adequate quality for playback. The word 'codec' (short for 'compress-decompress') is used for hardware or software that compresses or uncompresses graphic files.

14. Video disk array hardware

MiniDV deck: The Panasonic AG-DV2000 has a street price of about $2,200. See ad. in Videomaker.

15. Non-linear editing (NLE) software

Many digital video capture cards are also sold with NLE software. Some come with additional hardware, such as a breakout box to make cable connections easier and so on. This makes it difficult to compare one product with another. There is a 'Silver' list of DV & IEEE-1394 NLE software for PCs. CNET reviewed and compared, on 1 May 2001, five video editing programs in the middle price range: Adobe 'Premiere' v 6.0, Media 100 'CineStream' v 3.0, Sonic Foundry 'Vegas Video' v 2.0, Apple 'Final Cut Pro' v 2.0 and Ulead 'MediaStudio' Pro 6.0 and recommended 'Premiere' and 'Final Cut Pro'. 

For home and  semi-professional use

There is a comparative review in 'DV Magazine' October 1999, of 'EditDV' v 1.6, 'Final Cut Pro' v 1, 'Premiere' v 5.1 and 'Speed Razor' v 4.5.

For professional use

16. Computer video graphics cards that support two monitors

'Premiere' is easiest to use as video editing software, in a computer that has a video card which supports two monitors. There are several cards that support two monitors and work well with DVStorm:

17. Preview monitors, 'vector scope' and 'waveform' analysis

Videographers should check the quality of their video before they save it to the final format:

18. Digital video recorders (VCRs)

19. Retailers of video equipment and software

UK
USA

Check current US prices at Shopper and Pricewatch.

20. Books, magazines and journals

21. Digital video production companies

22. The camera, hardware and editing resources I have bought:

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© cspry@sghms.ac.uk. Department of Biochemistry & Immunology, St. George's Hospital Medical School, London SW17 0RE, UK. Phone +44 20-8725 5819; fax +44 20-8725 5821.