The K-5's live view implementation is almost identical to that of its predecessor the K-7, but whereas the K-7 was hobbled by a slow, unresponsive contrast-detection AF, the K-5 brings huge improvements. In general use, we have found that the K-5 is to all intents and purposes on a par with the Nikon D7000 as far as CD-AF is concerned. Neither is as fast as the Panasonic Lumix DMC-G-series, but both are significantly better than other DSLRs, and a lot better than the 'last generation' CD-AF of the K7. This makes a huge difference to live view shooting with the K-5, and greatly speeds up the process of establishing focus prior to commencing video shooting.
Live view is initiated using the dedicated 'LV' button on the camera's rear. Phase-detection AF is possible, but the improvements that Pentax has made to the speed of CD-AF mean that the latter is our default option. Two CD-AF modes are available - normal and face detection. If no faces are present in face detection mode, the K-5 defaults to a central AF point, which can be moved around the frame by pressing the 'OK' button and then shifting it using the left/right up/down keys of the 4-way controller.
In all exposure modes, the K-5's live view feed is kept to a constant 'correct' brightness, so does not simulate final exposure. An exposure scale is shown onscreen in manual exposure mode, and you can also opt to overlay a live histogram. However, counter-intuitively, this just shows the tonal distribution of the image on the LCD screen - i.e. not the estimated tonal distribution of the final image. In PAS modes, the LCD and histogram respond to any exposure compensation that you dial in (but again, as the histogram only changes to show the altered brightness of the live view image, it's necessarily a somewhat approximate guide to final exposure).
The K-5's live view image can be magnified in 3 steps, via repeated presses of the 'INFO' button on the camera's rear. After you have pressed 'INFO' once, you can also use the rear dial to zoom in further. None of the magnification stages give a particularly sharp screen image, and maximum magnification especially is perhaps a step too far, but even so it's effective enough for judging manual focus assuming a relatively high-contrast target.
The Pentax K-7 offered an unusual (or, depending on your perspective, distinctly odd) maximum video resolution of 1536 x 1024 pixels in the 3:2 aspect ratio. In the K-5, Pentax has decided to run with the majority of the DSLR pack by offering a more conventional (and much more versatile) 1920x1080 pixel capture at 25fps. Movies are stored using relatively inefficient Motion JPEG compression (with an AVI wrapper) and audio is supplied by an inbuilt monaural microphone, or an external mic if attached.
AF is not available during movie recording, and neither aperture nor shutter speed can be changed during recording either. A range of digital filters can be applied to movie footage, and some basic in-camera video-editing is possible too: clips can be trimmed and you can select and save individual frames.
|Sizes|| 1920x1080p: 25 fps
1280x720p: 25 fps/30 fps
640x424: 30 fps/25 fps
|Audio||Mono (Internal Mic), stereo recording possible with external mic|
|Format||Motion JPEG (AVI)|
|Max file size per clip||4GB or 20 min|
|Digital Filters||Cross Processing (3 presets), Toy Camera, Retro, High Contrast, Extract Color, Color.|
Using Movie Mode
Shooting a video on the K-5 is fairly straightforward, but not as streamlined an experience as we would like. To initiate movie mode, you simply turn the mode dial to the movie mode position and press the shutter button to start recording; press again to stop. Once the camera is recording it has complete control, and does not react to a press of any button other than the shutter button. AF is not available while recording video, therefore manual focus or pre-focusing by pressing the AF button before you start recording are the only options.
On the one hand, this means that there are no AF motor sounds to be recorded by the internal microphone as happens on other cameras. On the other hand, however, the K-5 looks a little under-specified in this respect. DSLRs are catching up - the Nikon D7000 and D3100 offer an effective 'AF-F' mode in video shooting and of course the Sony Alpha SLT-A55 can also perform full-time AF in movie mode using its phase-detection AF system.
Aperture, shutter speed and sensitivity are all set automatically. You can however choose to fix the aperture before you start the video capture, which gives you a degree of control over depth of field in your videos. In Auto Aperture mode the K-5 will adjust the aperture if the brightness of the recorded scene changes (the click sound is often clearly audible in the recording). In Fixed Aperture mode the camera achieves the same goal by only adapting the sensor sensitivity.
Unlike many of its competitors, the K-5 does not allow you to take any still images during video recording. You can't change the amount of on-screen information during video capture either. The camera's internal microphone records monaural sound, but if the soundtrack is important to your video there is also a connector for an external mic. The in-body image stabilization is activated by default but can be switched off.
Movie mode displays
|In the movie settings window you can change video resolution/quality as well as set whether the aperture is controlled automatically or manually, and shake reduction.||The amount of information shown during movie recording is fairly limited, but the important bases are covered - battery state, quality and time remaining, as well as shake reduction status and aperture.|
Video quality comments
In its 1080p full HD video mode the K-5 produces screen-filling footage with smooth motion that is in on par with other cameras in this class. In low light higher up the ISO scale the output gets noisier but compared to other cameras in its class the K-5 is very good in this respect.
The K-5's APS-C sensor gives you much more control over depth of field than you'll get from the vast majority of consumer video and digital compact cameras. While this allows you to use the focus creatively in an almost cinema-like fashion, on the downside it's very easy to record out-of-focus footage either by getting focus slightly wrong before video was initiated, or by your subject moving within the frame. For this reason, we consider the K-5 - like all DSLRS - to be generally better suited to creative videography than shooting a holiday or birthday video. For the latter you're typically much better off with a digital compact camera. Their smaller sensors provide a much greater depth of field and as a consequence the focus plane is much less of a worry.
Like pretty much all other video-enabled DSLRs the K-5 can suffer from distortion caused by its rolling shutter. The readout of the sensor means horizontal lines of the image are scanned, one after another, rather than the whole scene being grabbed in one go. The upshot is that verticals can be skewed if the camera (or the subject) moves too fast - the top of the image has been recorded earlier than the bottom, so vertical lines can be rendered as diagonals. On the K-5 this effect is relatively subtle compared to some of the competition, presumably thanks to a fast processor and sensor read-out. Transition from bright to dark scenes works pretty smoothly and quickly as well. exposure is smooth too - there are no jarring exposure 'jumps' as the camera adjusts the gain and/or aperture. Something to watch out for though is that when shooting handheld with telephoto lenses, the K-5's image stabilization system can be a little 'jumpy'. We still prefer stabilized footage to unstabilized, but ideally, for this sort of application, some sort of camera support is recommended.
Also be aware that the K-5's internal microphone is quite prone to wind-noise (there's no wind-cut setting) and handling sounds, such as lens zooming are clearly audible in the footage. If sound quality is a priority for you it's probably worth considering the purchase of an external microphone.
Caution: EXTREMELY large files
Sample video 1
This clip shows the K-5's video capabilities in low light conditions, and also gives some idea of the effectiveness of its image stabilization (shot handheld at 135mm).
|1080 x 720 25 fps, .AVI file, 10 sec. 67 MB|
Sample video 2
This is another low light clip that gives you an idea of how well the K-5 copes with panning.
|1080 x 720 25 fps, .AVI file, 10 sec. 52 MB|
Sample video 3
Another handheld shot, showing static and moving scene elements.
|1920 x 1080 25 fps, .AVI file, 10 sec. 133 MB|
Sample video 4
This video (again shot handheld at 135mm) contains a significant amount of wind noise - something to watch out for when recording video using only the built-in microphone.
|1920 x 1080 25 fps, .AVI file, 10 sec. 87 MB|