Canon updates EOS Final Cut Plug-in

Canon is showing the latest update for its EOS Movie Plug-in-E1 for Apple’s Final Cut Pro at NAB. The software provides quicker and easier editing of EOS Movie footage for FCP users.

The new version (1.2) will make importing EOS Movie files easier, allowing users to transfer files from any folder, without needing to mirror the folder structure on the camera itself.

It also enables smoother importing from Canon’s EOS 7D, EOS 5D Mark II and EOS-1D Mark IV models, allowing users to import footage without requiring the THM file generated by the camera.

The plug-in is designed to seamlessly convert EOS Movie footage into Apple’s high-quality ProRes 422 codec about twice fast as Apple’s standard conversion.

EOS Movie Plug-in-E1 for Final Cut Pro version 1.2 will be available to download free from 25th April 2011.

By David Fox

DSLR v Video: Why not both?

A matter of choice: Gollner and Davis (and Canon 550D DSLR)

HD DSLRs are now widely used for video production, even for prominent TV series and movie making. Users love the shallow depth of field and low cost of entry. But just how useful are they for professional production, how do they compare to low-end video cameras, and can they withstand the introduction of large sensor video cameras that give the same look but without the operational problems?

"The tones of the images, the look, the range of lenses, the animation capability – they make these cameras a dream for independent filmmakers, but they're not good for everything. For the videographer who gets paid to shoot, run around, be quick, gather audio, videos, interviews. Quick turnaround. Guaranteed results, meaning its not going to screw up; the DSLRs have proved far from ideal," said Rick Young, editor/director/cameraman, MacVideo.TV.

For him it's not a matter of choosing one over the other, "they're both fantastic," but of choosing the right one for a particular shoot.

Producer/director, Matt Davis, MDMA, has a Sony EX1, and wanted to do wider shots. So, he bought expensive wide-angle adapters, but then worked out that a Canon 550D costs less than the adapter, even including the wide angle lens (he bought a Tokina 11-17mm zoom, which he praises for its sharpness). "The wide angle experience has been absolutely monumental. It does everything that an EX1 can't. There is no droop at the sides. It's got this wonderful panoramic feel. It is a smaller camera that can get into smaller places." He is only now investing in longer lenses.

"It had to work with an EX1. It couldn't just stand on its own looking beautiful and arty. It had to play fair with the rest of the video family." He makes sure that both the DSLR and the EX1 are shooting within similar contrast ranges "It's close, but it's not exact. It still needs a little bit of finishing off in Final Cut," to match the two pictures, but that is now quick and straightforward.

When he cuts the two together, it is difficult to spot the difference. The blacks can give the DSLR footage away. The EX1 can use Cine Gamma to give soft ramping in the blacks, and the DSLRs don't necessarily have that exposure range. "They're pretty and they're good, but they have limits, and you really can't push beyond those limits like you can with a decent broadcast camera," said Davis.

"If you look at DSLRs in isolation they look fantastic," said Young. "But when you put it together [with video], that's when you can really see the difference."

Young has augmented his two Sony EX1Rs and two JVC HM100s with two Canon 5D Mark IIs with Canon 16-35mm and Sigma 12-24mm lenses, "and it's staggering what you can get out of it. And even if I only use the DSLR for nothing but those wide shots, it would suit a fantastic purpose. The cost of buying a serious wide-angle lens for conventional video technology would be more than probably buying the whole DSLR package," he told the recent MacVideo Expo in London.

"We need this technology. It doesn't mean that it is everything; it complements what we've got, but it doesn't necessarily take over," although it has become "an integral part" of the kit he needs.

RAW deal: Young in a still from a demo sequence

Overcoming limitations

"It's just another tool, and it's a very exciting tool," said Den Lennie, founder, F.Stop Academy, who shoots with a wide range of cameras from Digital Betacam to XDCAM EX and DSLRs. He has produced four training DVDs dealing with HD DSLRs, but they have not all been shot using DSLRs. The 5D Mark II training videos were shot on a Sony XDCAM 350, while the Canon 7D DVD was shot on an EX1 and 5D Mark II.

"The limitations of DSLRs particularly lie in the audio," and when he was shooting in Malaysia with Dan Chung it was essentially a two hour documentary, which would have been much more difficult to do if he had to use a separate audio recorder (see some clips from it at www.dslrvideoonassignment.com). However, the training video uses both EX1 and DSLR footage cut together, which works very well. "You really don't have to do a lot of work [in post] if you match your cameras up beforehand," he added.

He tends to roll the sharpness, contrast and saturation down on the 5D Mark II, and bring a little back in post if necessary, and also roll down the detail settings on the EX1. The fundamentals of the craft of filmmaking remain the same whichever you use.

Alex Gollner, producer/director/editor, Alex4D.com (who has created a wide range of free Final Cut plug ins), now uses a Canon EOS 7D and 5D Mark II as his primary cameras, only occasionally using video cameras.

He likes to use a DSLR because he so often has to interview people in small rooms where the background would be distracting if he didn't have shallow depth of field. It also allows him use a very small lighting kit, enabling him to set up more quickly. He doesn't do news style material with it, where he would choose his HDV camcorders.

DSLRs give "blurred backgrounds behind my interviewee" and a "touch of class" to the result, he feels.

He uses a Zoom H4n recorder for audio and gets his subject to clap. "Synching only takes a few moments, as long as I don't stop and start the camera too often, and make sure they answer in less than 12 minutes," due to the file length restrictions.

He generally uses the camera locked off and just zooms in in post for close ups, as 720p is what most clients want the video delivered in.

When shooting on the EX1, Lennie uses a Tiffen low contrast filter to help smooth out some of the contrast so it matches better with the DSLR. "It is much easier to shoot on video where it's necessary to shoot in difficult conditions or where you are working as a one man band rather than using the Zoom recorder." If he has to synch DSLR audio in post, he uses PluralEyes (www.singularsoftware.com).

He filmed a concert recently for The Skids on five 7Ds, where the 12 minute recording limit was an issue (similar to shooting on film), so they staggered the recording on each camera by about 30 seconds and stopped/started recording one by one at the end of each track, for a two hour shoot. "You make a decision on what's right for the project," he said.

Davis feels that there is space for both proper video cameras and DSLRs at the moment, until the large sensor video cameras establish themselves. "I definitely do need both because there is no such thing as a single perfect camera." He finds that people react differently to stills and video cameras. Sometimes, if they see a DSLR, they may pose as if for stills, so you can get less posed reaction shots with a video camera.

Lennie doesn't worry about rolling shutter effects, as it's not an issue for most of what he shoots, while problems with moiré can be countered by using filters or defocusing. "It's just a limitation of the technology." He feels that DSLRs are particularly good for shooting in the back of a cab or other confined space.

Even with the Panasonic AF101 and Sony F3 coming along, Young feels that DSLRs still have some advantages, such as their compact size. He finds all of his cameras equally useful and they are used for different things.

Reflecting on glass

One problem, said Davis, is that a 50mm lens is not really a 50mm lens on cameras that use APS-C (which has a 1.5x or 1.6x crop factor) or Micro Four Thirds (2x) sensors. "The standard lens on a full frame camera is quite a long telephoto on a Four Thirds camera."

However, he feels that investing in glass will hold its value. "Glass can be a long term investment. The back end doesn't matter. Think about the front end."

"My clients are not going to see too much of a distinction in between video quality" on these cameras, said Gollner. It's more his own pride that makes the difference.

"If the client's images look better and they are paying less or the same for a higher quality product, that makes you look good," added Lennie.

Gollner believes that he could possibly achieve the same with DV or HDV, but it would take some extra work. "I'm just getting better quality pictures for a little less work than I used to a few years ago."

"It's all about the pictures […] who cares about what the camera is," added Lennie, "It doesn't really matter what you shoot on if you know how to shoot well."

"For extreme wides and extreme beauty shots," DSLRs "can't be beat," concluded Young, but for most other things, especially long record times and having all the right controls in the right place, he turns to his video cameras.

This article first appeared in the December issue of TVB Europe magazine - the full issue is available to view online and download any pages as pdf files.

By David Fox

Beating budget bugbears and bitrates

There is a lot of really great technology being used on budget cameras – unfortunately, not all on the same camera…

Whether you are using an HD DSLR or any of the many compact camcorders, it is possible to produce very nice looking pictures. It isn’t easy and broadcasters might flinch from the results because some aspect of your camera doesn't meet their technical requirements for HD. However, the distance between the camera you have and the camera you need seems bridgeable. So, why isn't it being bridged?

At the HD Masters 2008 conference, Andy Quested, principal technologist, BBC HD, stated that he essentially wanted a camcorder with the front end of a Sony EX1 and the back-end of a Panasonic HVX 200 (or similar), as the BBC didn't believe that compact cameras with sensors of less than half an inch or inter-frame camera compression below 50Mbps were good enough for HD. Given that as the BBC goes, many others would follow, you'd think manufacturers would have rushed to produce something with exactly those specifications.

After all, there are an awful lot of Sony Z1 HDV camcorders out there (which were used to shoot observational documentaries and more in standard definition), and production companies are crying out for an HD replacement.

For that market, size is critical, as is ease of use. Price is also an issue, but less critical than you might think if the technology is right. However, manufacturers would prefer that broadcast users would buy their larger, more expensive models, which are not what productions need.

At the moment, the closest to the ideal seems to be the new Canon XF300 and XF305 camcorders, which are the most affordable cameras on the BBC's latest list of approved cameras for HD production – although they are only permitted for use by independent productions. The XF300 costs less than £6,000, while the XF305 (pictured) adds HD-SDI output, Genlock input and Time code i/o for about 10% extra. The other cameras on the approved list cost at least three or four times more.

The XF models are Canon's first Full HD MPEG-2 4:2:2 50Mbps camcorders (meeting one of Quested's parameters). They record MXF files to Compact Flash cards, and are highly compatible with broadcast post production. Most rival cameras record 4:2:0.

However, behind their 18x L-series HD lenses, the cameras have three 1/3-inch CMOS sensors. Although they are claimed to offer "exceptional colour accuracy, wide dynamic range and low noise" and use high-speed data readout (2x speed) to minimise the rolling shutter skew common to most CMOS camcorders, the sensor size isn't ideal.

The cameras also offer slow and fast motion recording, with 20 speeds to choose from in 720p mode and nine in 1080p (normal recording speeds are 1080 50i or 25p, 720 50/25p (in the European versions). The upcoming Canon XF100 and XF105 use the same recording system, but have only one CMOS sensor, which will inevitably diminish picture quality - even if that won't be evident to many viewers. However, their size seems perfect for typical self shooters.

Sensor sensibility

What many productions would like are larger sensors. Much larger. Conventional broadcast cameras tend to use three 2/3-inch sensors, but HD DSLRs usually use a single APS-C sensor (some 5.5 times larger and roughly the size of a 35mm movie frame). This gives very shallow depth of field and permits the use of a wide range of excellent lenses that are often relatively inexpensive (by video standards). Some DSLRs, such as the Canon EOS 7D, can also be fitted with PL-mount cine lenses.

The results can be excellent. However, there are lots of compromises to be made. The latest slew of HD DSLRs from Sony, Nikon and Canon suffer from a range of "features" that can frustrate anyone trying to use them for serious video production.

The recording bitrate on HD DLSRs and budget camcorders is almost invariably too low. The Canon 550D/60D/7D trio are about the best of the bunch, recording at 44Mbps, but Sony's DSLRs record using the more efficient AVCHD, but at just 17Mbps (despite the fact that the AVCHD standard goes up to 24Mbps). Nikon hasn't revealed official figures for its new D3100, but our testing showed about 20Mbps on a pre-production model. At the very least both should have aimed for 24Mbps.

Panasonic's micro-four thirds cameras are similarly constrained – despite the fact that its consumer camcorder division makes a little three CMOS camcorder, the SD700, that records AVCHD at 28Mbps (at 50/60p).

Both Panasonic and Sony also seem to have settled on AVCHD at 24Mbps for their compact professional camcorders, such as Sony's NXCAM or its upcoming DSLR-based Handycam NEX-VG10E (pictured). When Panasonic first showed a mock-up of its forthcoming 3D camcorder it had an AVC-Ultra logo (which would have meant recording up to 200Mbps), although AVC-Intra (at 100Mbps) would have been more than acceptable. Instead, the AG-3DA1 records 24Mbps AVCHD when even its consumer Mini-Me version (the new SD700-based HDC-SDT750) records at 28Mbps…

Bitrate hacked

The improvement a higher bitrate can make is easily seen on Panasonic's GH1 camera. It has been hacked to record at higher bitrates.

Andrew Reid of eoshd.com shot a test on the GH1 at ISO 1600 using both 1080/24p AVCHD at 44Mbps and 720/30p MJPEG at 70Mbps – both show a considerable improvement over the standard 17Mbps, although the AVCHD is a clear winner.

EOSHD GH1 High Bitrate Test - Low Light from Andrew Reid

Of course, HD DSLRs have other hurdles to overcome, not least aliasing and moiré patterns, which are evident on Reid's video. Panasonic promises to address this problem with the new AG-AF100 / AG-AF101 camcorder, which is based on the Micro Four Thirds sensor and lens system used by the GH1. However, the AG-AF101 is also limited to AVCHD 24Mbps 4:2:0. It also appears that Panasonic may have taken action to prevent the hack working on the most recent shipments of the GH1, so the AF101 may not be hackable either. Perhaps Panasonic should offer its own 44Mbps (or higher) version at a reasonable mark up.

The NEX-VG10E and AG-AF101 are just the first of several DSLR-inspired cameras coming over the next few months, and hopefully will inspire the likes of Nikon and Canon to respond with more video-friendly features, such as peaking and zebras to aid focusing and exposure, anti-aliasing, better audio controls, those higher bitrates or, at least, HDMI interfaces that allow non-compressed video to be recorded in a nanoFlash or similar higher bitrate recorder. CMOS sensors with less pronounced rolling shutter defects would be nice too.

Despite the problems, the artistic possibilities of HD DSLRs and their ilk can make all the hassle worthwhile. Canon's 5D Mark II, with its even larger full-frame 35mm sensor, was used to shoot the finale of last season's run of House. It had a noticeably different look to the standard film production, but worked well for what they wanted it to do. For the upcoming season of House the 5D will be used routinely on episodes, especially when they want a more intimate look. This certainly proves that the rapid adoption of HD DSLRs has not just been for cost reasons. It certainly hasn't been for ease of use….

By David Fox

Canon EOS 60D - more of the same

The new Canon EOS 60D has been designed to fill the gap you hadn't spotted between its existing EOS 550D and EOS 7D video-friendly models.

The end result will, in video terms, be essentially the same. However, it has a few new features that 7D owners (us…), will wish for, and might tempt some would-be 550D buyers to spend a little extra.

The most obvious feature is its articulating LCD screen, which will make it a lot easier to get low- or high-angle shots.

It also has full manual control of video settings, which is certainly nice creatively, and manual audio controls with the ability to turn off automatic gain control (it also has a stereo mic input), which would be a jolly useful addition to the external audio recorder you'll probably need to have anyway.

Otherwise, the picture quality (stills and video) seems to be unchanged from the 550D/7D. Is it a less expensive 7D without the tank-like build quality and a couple of features useful for stills, or a more expensive 550D with extra features and better build quality, or both…?

Specs: it records 1920x1080p HD video at 24, 25 and 30fps or 720p video at 50 and 60fps onto SDXC cards, using the MPEG-4 AVC, H.264 codec (.mov files) at 44mbps. It will list at $1,100 (body only) or $1,400 (with 18-135mm kit lens – a very nice lens with a useful range for video).

Canon has also announced an updated version of its EOS E1 plug-in for Apple's Final Cut Pro with support for the 60D. It converts recordings into ProRes 422 at least twice as fast as Apple’s standard conversion and allows logging with timecode, reel names and metadata. It also provides support for multi-core processing, for faster conversions on higher-powered Macs. It already works with the Canon 5D Mark II, 1D Mark IV, and 7D.

By David Fox

Transparently Sony for HD snappers

Sony has announced new HD DSLR cameras that record 1920x1080 video, with some interesting new features and the usual bitrate stupidity…

The Sony A580 and A560 models will be its first DSLRs to do video of any sort. It also has two Single Lens Translucent cameras (DSLRs without the reflex), which use a pericle mirror to deflect some light up to a fast phase-detection auto-focus sensor while still letting about 70% of the light through to the image sensor.

Sony Alpha A580

The 16.2 megapixel A580 and 14.2mp A560 use Exmor APS-C HD CMOS sensors with enhanced Bionz processors. Both have 3-inch pivoting LCDs and good low-light capabilities (up to ISO 25,600). The €900 A580 will be available in October and the €800 A560 ships early 2011.

The fixed, semi-transparent mirror in the SLT A55 and SLT A33 (pictured top) means that they can use their faster, more accurate phase-detection AF sensor all the time, including video mode. HD DSLRs can only use phase-detection in stills mode (while the mirror is down), because the mirror has to be locked up for video, which requires switching to slower, less accurate contrast detection AF (which isn't even available during recording on some cameras and is so slow it is almost unusable on others).

Typical Sony A55 users

Of course, users should really be skilled enough not to have to use any fancy auto focus. They should be capable of doing everything in manual, including, no doubt, hand cranking the shutter…. :^)  While manual focusing is probably the best way to shoot many subjects, it isn't always easy to focus precisely with stills lenses, especially if you want to adjust it seamlessly during a recording, because the focus mechanisms aren't as precise as they are on a dedicated cine lens – and the cameras don't have the focusing aids you might expect on a professional camcorder (such as peaking). Most DSLRs don't give you much manual control over any functions during recording (these only allow you to adjust the aperture), so the quality of their automatic controls is important.

As the SLT cameras don't have to retract the mirror to take stills, they can also be used at high frame rates for photography (up to ten frames per second on the A55), and the cameras are significantly smaller than DSLRs. Although less light gets through to the CMOS sensor, this reduction is only the equivalent of about half a stop.

Sony A33 makes a splash

The 16.2mp A55 ($749 October) and 14.2mp A33 ($649 September) have a 3-inch articulated LCD, and go up to 12,800 ISO. All the cameras have HDMI output and mini-jack stereo microphone input.

All four Sony cameras record 1080 50i/60i (25p/30p capture on the sensor), using AVCHD at only 17Mbps, which is daft. When even its Handycam camcorders can record AVCHD at 24Mbps, why is Sony crippling these cameras by limiting them to 17Mbps?

Even so, it looks as if they can record reasonable video – have a look at the ever-excellent DP Review in-depth review of the A55, which has unconverted files you can download – the sixth clip is a great example of the jello effect you can get with a rolling shutter.

Given that for a similar price you can buy Canon's EOS 550D, you'd be nuts to buy any of these Sony cameras if you want to shoot video; but as consumer stills cameras (or even prosumer in the case of the A580/A560), which also shoot home videos, they could be worth considering.

By David Fox

HD DSLRs - the film look on a budget

One of the most exciting developments of the past year, for those whose ambition is larger than their budget, has been the introduction of HD DSLR cameras that offer large sensors and a huge range of lenses for less than the price of a Sony EX1.

It was notable that about half of all the cameras on show at the February Broadcast Video Expo in London were HD DSLRs – the previous year there had only been one (on the Canon stand). Low-budget filmmakers were the first to realise the potential, but now programmes you might have heard of are using them.

For the rest of this article, read my full piece on HD DSLRs from the May issue of TVB Europe magazine in: HD DSLRs - the film look on a budget

The photo above is of Rodney Charters, cinematographer on 24, and Sam Nicholson, 24's visual effects supervisor, who are quoted in the article about their use of HD DSLRs on the series.

David Fox

Cine lenses for HD DSLRs

Carl Zeiss is creating a set of prime (from 18mm to 85mm) and zoom lenses for HD DSLR cameras.

Its upcoming Compact Prime CP.2 and Lightweight Zoom LWZ.2 lenses will have interchangeable mounts that can be used with Canon EF, Nikon F, and PL-mount cameras.

The primes can be used on full frame cameras (like the Canon 5D Mark II), and will all open to T2.1 (although in the press photograph of the lenses, the 85mm is shown as a T1.5). However, the 15.5-45mm/T2.6 zoom lens can only be used with crop sensors (such as on the Canon EOS 7D – up to 24.9x18.7mm, a Super 35mm film frame). The zoom will weigh about 2kg, which makes it useful for Steadicam applications. Thanks to the interchangeable mounts, the lenses should be very attractive to hire companies, as they will cover a wide range of traditional cine cameras and HD DSLRs.

Prices are likely to be at least as much as many of the cameras they are fitted to, and they should be available from June.

Being designed for moviemaking, they will be a lot easier to use than stills lenses, especially for focusing, with longer focus rotation (making it a lot easier to be precise – particularly for manual use).

The iris opening in the prime lenses uses 14 high-precision blades, which stay consistently round and symmetrical over the entire T-stop range. This should translate into natural and pleasing out-of-focus highlights and a smooth bokeh (the ring around the blurred highlights). The lens design and tight tolerances are claimed to "ensure low distortion, high resolution and excellent colour rendition for sharp, punchy images."

By David Fox

Canon cuts cost of HD

Canon has introduced a new, entry-level HD DSLR that will cut the cost of shooting full HD, taking it well below the price of any semi-professional camcorder. The new EOS 550D (Canon Rebel T2i in the US) camera will probably be available for under £800, including a kit lens, when it ships on February 24.

It uses a newly developed 18 Megapixel APS-C (22.3x14.9mm) CMOS sensor (more than five times the size of the 2/3-inch sensors commonly found in broadcast cameras), with Canon’s advanced DIGIC 4 14-bit image processor, as used in the larger 7D (which we used to shoot our video at the Canon event).

Users can record 1920x1080 at 24, 25 or 30 frames per second, or 720p at 50 or 60fps. As seen with the 7D, the 550D Rebel T2i should produce excellent pictures in low light – it can record at ISO settings of 100 – 6400 (expandable to 12800), with noise reduction delivering clean looking images. It also has a 3.5mm stereo microphone socket for an external microphone.

Highlight tone priority can be set independently for movie capture, without changing any still image capture settings. The 550D Rebel T2i also has a new Movie Crop function that records with the central 640x480 pixel area of the sensor, giving 7x magnification, however this isn't available for HD recording (where it would probably have to be 4x or 5x – perhaps an HD version is something for the future).

From an ergonomic point of view, the smaller size, and lighter weight (530g body) of the 550D Rebel T2i, may make it easier to hold than Canon's existing, larger, HD DSLRs.

For video output, there is a mini HDMI port, but this doesn't give access to the uncompressed video signal (for recording to an external recorder). Recording, to a SDHC card, uses the .MOV format with H.264 video and Linear PCM audio at 45Mbps (for a maximum duration of 30 minutes or 4GB file size).

There is also a 3-inch 720x480 pixel LCD screen (which has to be used in video mode as the conventional viewfinder can't be used because the internal mirror is locked up).

Plugging in to FCP

Canon has also announced a new EOS Movie plug-in for Final Cut Pro, to enable quicker and easier editing of EOS footage. A free Beta release of the plug-in will be available to download in March.

The plug-in will enable the log and transfer of video footage from the EOS 5D Mark II, EOS 7D, EOS-1D Mark IV and the 550D, and convert the recordings to Apple’s high quality ProRes 422 codec at approximately twice the speed of Apple’s standard conversion. Users will also be able to add timecode, reel names and metadata.

Related posts: HD DSLRs: Still developing and HD DSLRs: nice pictures, nicer price

By David Fox

HD DSLRs: nice pictures, nicer price

One of the most exciting developments of the past year, for those whose ambition is larger than their budget, has been the introduction of HD DSLR cameras, most notably from Canon. These allow the use of lots of relatively cheap, high-quality lenses with an APS-C (about 23x15mm) or even 35mm (36x24mm) sensor that can capture beautiful images for less than the price of a Sony EX1 or other low-budget professional camcorder. The APS-C sensor has about 5.5 times the area of a 2/3-inch sensor used in most mainstream broadcast cameras (and about ten times the area of a half-inch sensor used in the EX1 - although broadcast cameras usually have three such chips so performance isn't exactly comparable).

As HD DSLRs are designed primarily for stills photography, they don't have the ergonomic layout you'd expect from a video camera, and there are limitations in what controls you can use while recording and in facilities (especially audio). The choice of recording codecs is not always ideal either. But low-light performance is often excellent, and they are particularly useful for stop-frame animation or time-lapse videos.

Virtually all CMOS sensors used on DSLRs (as with most low-end camcorders) exhibit rolling shutter artefacts (when the camera is panned any vertical lines in the picture will wobble while photographic flashes may only occupy part of the picture). High-end digital cinema camcorders typically use a global shutter (which electronically shutters all pixels simultaneously) or simply readout fast enough from top to bottom to reduce or avoid it. However, it is certainly a problem with the current crop of HD DSLRs, necessitating slower panning speeds, the use of Steadicams or shake reduction technology for hand-held shots, or fixing the problem in post, with the likes of The Foundry's RollingShutter plug-in for Nuke and After Effects (watch a video about RollingShutter).

A further issue is audio. Many of the higher-end cameras have a mini-jack input for mono or stereo audio, some rely on inadequate built-in mics. However, it is generally best to work with them like a film camera and record audio separately.

There are also restrictions on the length of clips that can be recorded at one time (12 minutes on the Canon EOS 7D, for example), possibly to avoid sensor heating or power problems, and users have to be careful to buy memory cards that are fast enough that they will record all the way through without problems (there can be a big difference between card manufacturers on this, with some performing better at a lower stated class than others do at a higher classification).

If you're wondering what difference would it make buying a 35mm sensor over an APS-C or broadcast 2/3-inch sensor camera: 35mm will give you shallower depth of field (less of the picture in sharp focus - and more of it, especially the background, pleasingly blurred). However it can also be a nuisance. You can set up a shot, have the subject perfectly in focus, start shooting and he's moved back or forward slightly and is now out of focus. In most situations, you'll be able to get as little depth of field as you'll ever need with an APS-C sensor (and often even with 2/3-inch chips). Of course, the larger the sensor, the better quality image you should get - especially in low light, as the pixels aren't as closely packed together (but a 25megapixel 35mm sensor will have about the same pixel density as a 10 or 11MP APS-C sensor), and you're only going to be shooting at 1 or 2MP for HD video - so how the recording codec performs may have a bigger impact on your video quality than the sensor size.

Playing the field

The camera that started this trend is Canon's EOS 5D Mark II (the first 35mm HD DSLR - pictured top in use with a Vocas DSLR rig), which is ideal for anyone who wants shallow depth of field at the lowest price possible.

It currently records 1920x1080 at 30 frames per second (which has been a problem for those of us in Europe, although that can be dealt with – look at filmmaker Philip Bloom's website for suggestions). However, that will be rectified early in 2010 when Canon promises to update its firmware to allow 24 and 25fps. It has already updated the camera to allow full manual exposure while recording video.

[UPDATED: The 24/25fps update (firmware 2.04) is now out and also adds full manual audio controls.]

The new Canon 1D Mark IV already has full HD at 24, 25 and 30fps (plus 720p/50 and 60), but uses a slightly smaller 1.3x crop sensor (APS-H - although its performance in low light seems to be particularly good). The recently introduced Canon EOS 7D offers the same formats on a less expensive APS-C model (about 1.5x crop). Files are saved using AVC/H.264 compression in a .MOV container (at about 44Mbps for full HD), with Linear PCM 48KHz audio.

[UPDATED: There is also now the Canon EOS 550D (Rebel T2i in the US), which is smaller and lighter (and about half the price for the body) than the 7D, but offers the same video formats on the same sensor - although it isn't as feature rich as a stills camera as the 7D.]

Although Canon is the key manufacturer of HD DSLRs, others have entered the market.

The APS-C Nikon D90 was the first DSLR to record HD video, at 720p/24, as now do Nikon's 35mm D3S and APS-C D300S and D5000 models, using AVI Motion-JPEG codecs.

The compact Pentax K7 is another APS-C 720p camera, but only at 30fps (AVI Motion JPEG at about 45Mbps variable), although it can also shoot at a non-standard higher resolution (1536x1024 - 3:2 aspect), however the even smaller Pentax K-x records 720p at 24fps, has very good low-light performance, and is currently about the cheapest HD DSLR available. Both Pentax models benefit from in-body shake reduction, which means that they can be used hand held with inexpensive, old prime lenses.

The Panasonic Lumix DMC-GH1 has an interchangeable mirrorless lens system, which means it can be smaller than conventional DSLRs, although it also has a smaller (Micro Four Thirds) sensor with a 35mm crop factor of about two. It seems to be the only "HD DSLR"* that can auto-focus while recording video, although that should be less important for anyone coming from a video or film background than it seems to be for stills photographers moving up (although autofocus only works with certain lenses). It records 1920x1080 at 50/60i or 24/25p using AVCHD (about 17Mbps), or can record 720p/50 AVCHD or 720p/25 using Motion JPEG (.MOV at about 28-30Mbps). Tests show a lot more artefacts in 1080 than with 720, which isn't surprising as the bitrates are the same. There is also the cheaper Panasonic GF1 which only records 720p/60 and 30.

*Note: Of course the Panasonic isn't a DSLR - as it doesn't have a mirror (the Reflex), but as it has interchangeable lenses it should probably be included here....

Related Posts: Cheap 35mm video - Canon cuts cost of HD - HD DSLRs: Still developing

By David Fox