Yesterday saw my stills shootout between the Lumia 1020 and the Android-powered Galaxy K Zoom - today sees the video equivalent. Being able to capture videos anytime, anywhere, is something that all of us do. And, to be fair, most modern smartphones do a great job at this. But what happens when you want to go further, zooming in and out and generally pushing the boundaries? In split-screen presentation, here's video from (arguably) the two best video capture phones around.

Yes, the Apple iPhone 5S can do fancy slow motion effects, yes, the Xperia Z2 can shoot in 4K (for a few minutes, before it overheats), but these two devices have something special. Optical image stabilisation (OIS), for a start, making a huge difference, and genuine lossless zoom. Digital in the 1020's case, thanks to the underlying 41MP sensor, and optical in the K Zoom's case. Plus two of the largest sensors in the phone world, gathering light.

The optical zoom system is undeniably (though understandably) bulky though:

Let's kick off with the video comparison directly. Both smartphones can record in 1080p (16:9) resolution, obviously, though in order to see real time differences, I've used my video editing software (iMovie on the Mac) to create a split screen effect, with each half of the 1080p frame representing the middle 50% of each smartphone's full frame.... oh, heck, you'll get what I mean the moment you start watching the video.

Also, note that the video below was (necessarily) after compression of the video by my editing software and after re-compression by YouTube's own internal algorithms. So the raw quality, especially in low light, of each smartphone is slightly higher than it appears in the comparison. Do please make sure you make allowances for this.

As you're trying to spot differences and be generally picky about quality, make sure you have a nice fast connection and a large screen. And then maximise the quality to 1080p in the YouTube settings ('gearwheel') pop-up:

The scenes/tests above are, in order:

1. Walking along a gravel path
   Testing OIS to the extreme, I wouldn't expect any OIS system to be able to cope with a walking gait, but I was still interested to see how well or badly each device behaved. The 1020's larger OIS system (based around a 1/1.5" sensor) and optics just about win out here, but there's really not much in it.
2. Panning slowly around a graveyard (way to keep things cheerful, Steve!)
   Looking at OIS stability and detail/colour. The 1020 just has the edge in the latter, thanks to superior optics and to the vibrancy of the colour handling. The K Zoom's more muted greens perhaps underplay the colours my eyes saw, but I know which world I'd rather live in! On the other hand, the K Zoom's OIS keeps the pan incredibly smooth here, so honours even overall.
3. Down by the lock, zooming in a boat around 40m away
   A clear win for the K Zoom here, unsurprisingly, with the 10x optical zoom producing astonishing capability (for a phone) and pretty decent stability, even when zoomed in. When zooming out back to 4x, the OIS in the K Zoom is so effective that the footage could almost have been shot on a tripod. In contrast, the Lumia 1020 does well, but typical Nokia Camera autofocus hunting 'pops' mar the image, the 4x zoom pales compared to the 10x optical, plus the OIS does a worse job at evening out the tiny hand wobbles in this use case.
4. At the other end of the lock, shooting 1:1 and then zooming in to detail on a cottage
   Both handsets do well here, honours even. Most of the shaking in the footage was me fiddling with the screen and buttons in order to effect the zooming, by the way! Audio is switched to the K Zoom for this clip and the next, and there's little difference in quality between the two devices.
5. A duck on the water(!)
   Shooting zoomed in by 4x and then (on the K Zoom) by 10x, the difference in closeness and framing is obvious.
6. Low light footage inside a church
   Starting with similar quality, the 1020's auto-exposure gets thrown somewhat by the light through the stained glass window, plus focus and detail isn't perfect. The K Zoom, on the other hand, performs better than expected, with stunningly clear zoomed detail on the glass window. In fairness to its auto-exposure algorithms, the 1020's centre of vision seems to have been the dim altar, while the centre axis of the K Zoom camera was very slightly higher, on the bright window, so take this comparison with a pinch of salt, other than the conclusion again that optical zoom is better than digital zoom when you need a lot of it!
7. Macro of blossom
   I had to shoot this freehand and sync my movements, because - obviously - when shooting on a split-screen jig, the devices are separated by 20cm or so and thus have different viewpoints. Both devices produce very decent results here, with the 1020 winning on colour handling and the K Zoom winning on focus stability and detail.

Overall, it's hard to split the Lumia 1020 and K Zoom for video capture. Each has its pros and cons:

The noise of the optical zoom is interesting - it's certainly not intrusive, but definitely is audible. There's a 'silent zoom' setting in the K Zoom's software, and this attempts to cancel out the mechanism noise digitally - at the expense of also taking out those frequencies and volume from your subject too - it's a definite 'no no' when shooting music, for example.

Also notable is that the K Zoom, like the S4 Zoom before it, has similar HAAC stereo microphones to the Lumia 1020. I tested the S4 Zoom last year in a rock gig and was astonished to find the audio from the Android device as good as that from the 1020 - so kudos to Samsung here and - hopefully - it hasn't infringed any Nokia patents along the way! [I'll be testing the K Zoom at a  gig this weekend and I'll amend this article if there's a difference in capture performance between the S4 Zoom and K Zoom, of course.]

Having shown the footage above to others, there's a split in opinion as to which device is 'better' for video capture. I think it depends on how much/often you need to zoom. The 1020 produces admirable output with some zoom when needed, all in a phone body that's relatively slim, while the K Zoom excels when zoomed to even extreme lengths, at the expense of bulk when not in action and significant physical extrusion when in use, as shown in the photo at the top of this piece.

Apologies for sitting on the fence then, here. But, as with stills capture, it all depends on what you plan to shoot on your smartphone camera!