Mike Chaney's Tech Corner

Technical Discussions => Articles => Topic started by: admin on June 30, 2009, 05:08:07 PM

Title: July 2009: dSLR Video Revisited
Post by: admin on June 30, 2009, 05:08:07 PM

July 2009: dSLR Video Revisited


In January I wrote an article about the video capabilities being offered on a handful of dSLR cameras.  In the 6 months since publishing that article, Nikon, Canon, and Panasonic have released new dSLR cameras offering high definition video capabilities and with each model, those capabilities get more and more refined.  It seems clear at this point that HD video has graduated from being a nice feature to a necessity when buying a newly released dSLR.  But many are still wondering as they did six months ago: is it time to retire that old HD camcorder?


The Allure of dSLR Video

So what's the big deal about dSLR video anyway?  Why would you want to video with a dSLR rather than an HD camcorder?  Simply put, many feel that the larger sensors in dSLR's give a shallow depth of field that looks more like film than video.  Most consumer HD camcorders record video where foreground (subject) and background are in focus at the same time.  This deep depth of field has a sort of "video feel" to it.  In contrast, if you are watching a feature film in the theater and you are watching a scene that includes a closeup of some subject, you'll likely notice that the subject is in focus and the background is pleasingly blurred.  The ability to make your subject stand out from the background is something dSLR video can offer that HD camcorders often have a difficult time accomplishing.

When dSLR video finally hit the consumer mainstream starting with the Nikon D90 and Canon 5D Mark II, you started seeing shallow depth of field videos from all over the world where people were shooting random scenes and then muting the sound and adding their favorite music (illegally in most cases I might add) for effect.  Shooting these shallow DOF "music videos" has become the latest fad, powered by the consumer video capable dSLR.  When tastefully done, it can present an almost larger than life view of certain subject material but more and more it is just becoming a competition to see who can get the most shallow depth of field and add some cool music.  In my opinion, there's only so much of that you can watch until it starts to dilute what the depth of field effect is trying to accomplish in the first place.  Hopefully this "shallow depth of field music video fad" will taper off over time and we can get back to using that effect to highlight our subjects rather than oversaturating ourselves to the point that it goes unappreciated or unnoticed when it is truly called for.  While my view is that shallow depth of field videography should be used a little more sparingly than it is in current trends, it is something that dSLR video can accomplish where most camcorders fall short.  Even though it can be overused and abused at times, shallow depth of field when applied to appropriate scenes can promote your videos from video capture to true cinematography!


At a glance: dSLR and dSLR-like cameras that offer video

Canon 5D Mark II: As would be expected for a camera of this caliber (and this price range), video quality is exceptional.  With it's full size (35mm) sensor, the 5D Mark II offers the most film-like video quality with shallow depth of field and pristine quality even in low light.  The 5D Mark II is, however, more geared toward the professional videographer as it only offers manual focus while shooting video.  In addition, the built in audio mic sits right above the lens and if you are using an image stabilized (IS) lens, the mic will pick up the noise from the image stabilizer so using an external mic is a requirement if you want to capture hand held video with an IS lens.  This is probably not a good choice if you are looking for a walk around video device.

Nikon D90: The first real dSLR to offer HD video, the D90 offers 720p HD video capture but like the 5D Mark II, does not offer continuous autofocus.  Audio quality is not as good as the 5D Mark II due to the low sample rate but is usable.  A first generation implementation of HD video in a dSLR, the D90 is an interesting and affordable entry into the field but like the 5D Mark II, will likely not be your choice for a walk around video camera due to lack of automatic controls.

Nikon D5000: The second generation Nikon dSLR to offer HD video appears to be an updated dSLR with D90 video added in.  Specs are nearly identical to the D90.  Both the D90 and D5000 do well at their mainstay: dSLR photography.  Like the 5D Mark II and D90, the D5000 is a camera that most people will likely use to shoot great photographs, using the video only as an added bonus or for special purposes like creative/staged production work.

Canon 500D: The Canon 500D offers full progressive HD quality video (1920 x 1080) but only at 20 frames per second.  For video with even moderate motion or panning, users may prefer the faster 720p mode at 30 fps.  Audio quality is OK using the built in mic but there is no external mic jack on the 500D.  Like the 5D Mark II, the internal mic picks up the IS lens noise and autofocus noise so while you can press a button to autofocus while in video mode, the mic will pick up the sound and you'll see an abrupt change in focus in the video and potentially some focus "hunting".  Simply put, it's not like the autofocus on your typical HD camcorder.

Panasonic GH1: While technically not a dSLR because it has no mirror or optical viewfinder, the GH1 operates much like a dSLR camera and produces similar results.  Due to removal of the mirror which blocks light from the main sensor for functions like autofocus, the GH1 was designed more with video in mind.  Fast autofocus during video and an articulating rear LCD make the GH1 easier to operate.  With stereo microphones built in to the top flash unit, the camera can record good quality sound without interference from autofocus mechanisms or IS lens hardware.  With the 14-140 kit lens, the GH1 also offers a 10x zoom which is comparable to many hand held HD camcorders.  Video compression artifacts render the full (1080) HD mode nearly unusable for anything but slow moving subjects, but the 720p HD modes offer excellent quality.  The Mega OIS 14-140 lens also offers image stabilization that appears to be more capable than competing manufacturers as it is designed with video stabilization in mind.  With the Micro Four Thirds sensor being somewhat smaller than the D90, D5000, and 500D APS-C size sensors, the GH1 won't give you depth of field that is quite as shallow as the competitors but certainly better and more film-like than nearly any HD camcorder.


The Big Picture

There are some areas where an HD camcorder simply works better than any dSLR.  No current dSLR can compete with the one-handed ease of zooming found on HD camcorders and there are still some technical details yet to be worked out on video capable dSLR cameras.  All of the current dSLR cameras suffer from rolling shutter or "video jello" effects that cause objects to warp or bend during fast panning although the effect is usually not noticeable on anything but ridiculously fast left/right swings: something you don't normally do in video.  In addition, most HD camcorders respond more smoothly to lighting changes whereas the dSLR cameras can sometimes produce a more "stepped" look to lighting/exposure changes.  Certainly most if not all yet-to-be-released dSLR cameras will offer HD video in coming months, so expect things to change quickly.  As a non-pro videographer myself, I don't do many staged videos where I can manual focus and shoot from a tripod as would be done in a commercial or short film.  As a result, when compared with your typical hand held camcorders, the current offerings from Nikon and Canon operate more like a "hack" when it comes to video.  They offer shallow depth of field and film-like quality that camcorders cannot accomplish but at the same time they are not very easy to use in the field.  Part of the problem with video on typical dSLR cameras is that with their mirror and prism, they just weren't designed for real time video.

The GH1, on the other hand, feels more like a camera that was built from the ground up with video in mind.  Offering super fast and continuous autofocus and an articulating LCD that can be used when holding the camera at odd angles, the GH1 is currently the closest match for replacing your camcorder.  That said, don't expect to pick up the GH1 and shoot it like you would a camcorder.  Most camcorders can be operated with one hand even when zooming.  The GH1, with its manual zoom, is a two handed camera and unless you're willing to put in a lot of practice and have a steady hand, you're not likely to see those super smooth zooms you get from an electronic zoom mechanism on a camcorder.  That said, the GH1 is rather forgiving when it comes to large sensor video capture devices.  Video quality is not quite up to par with competing camcorders in full 1080 HD mode due to the panning and motion artifacts that appear in that mode, but it is possible that future firmware updates will solve that issue and until that time, the 720p video modes work very well on the GH1.  The GH1 also has a size advantage in that it is smaller and easier to carry than its competitors.  For many of us in real world situations, that can mean a greater chance that you'll actually have the camera with you; you can't take photos or video if you left the camera home because you didn't want to deal with the bulk.



dSLR video is "the next big thing" in dSLR type cameras.  I see a lot of people upgrading to the next model just to get video, so I want to make sure people are aware of the pros and cons of using certain model cameras as a replacement for an HD camcorder.  As of this writing, the Panasonic GH1 is the only large sensor camera that can be used like an HD camcorder by your average consumer.  There are some new cameras that offer HD video like the Canon SX1 but due to smaller sensor size, they don't really perform like an SLR as far as being able to shoot creative video.  The Panasonic GH1 is currently leader of the video pack when it comes to ease of operation and usability in real world conditions, making video implementations from competing dSLR's look more like "video hacks" than true integrated functionality.  I'm under no illusion, however, that dSLR video is evolving.  I suspect by fall or early winter, we'll see video capability mature in dSLR or dSLR-like cameras from all manufacturers.  There are already some soon-to-be-released competitors to keep an eye on like the Pentax K-7 and the Olympus E-P1 with many others just around the corner.


Mike Chaney

Title: Re: July 2009: dSLR Video Revisited
Post by: Fred A on June 30, 2009, 07:07:37 PM
I assume that the amount of (minutes) video depends on the memory card?
What is currently available in terms of gigabytes/time at what resolution?
Really sounds like things to come in our future.

Title: Re: July 2009: dSLR Video Revisited
Post by: jeffjessee on July 03, 2009, 07:21:37 PM
>What is currently available in terms of gigabytes/time at what resolution?

Fred-On the Canon 5D Mark II, it actually depends on the OS. File size is limited to 4 gig, which gives about 12 minutes of 1080P video, or about 24 minutes of 640x480 video (it would appear they don't compress the 640x480 video as much, if one can believe the manual. I haven't shot 24 minutes yet to test). But you can just stop and restart anytime to begin a new file.

Title: Re: July 2009: dSLR Video Revisited
Post by: admin on July 03, 2009, 08:07:57 PM
With the Panasonic GH1, you are only limited by the size of the card (for the U.S. version of the camera).  A 4 GB card will let you shoot about 30 minutes of video.  Use a 16 GB card and you get 2 hours, and so on.


Title: Re: July 2009: dSLR Video Revisited
Post by: slomo on July 16, 2009, 05:36:37 PM
Is there a way to get around the 20 minute time limit on the d90s video compatibility?

Title: Re: July 2009: dSLR Video Revisited
Post by: admin on July 16, 2009, 10:11:44 PM
Is there a way to get around the 20 minute time limit on the d90s video compatibility?

I don't think so.  I believe that's a limitation of FAT32 and the file/storage format.