Inside the HTC ultrapixel hype

HTC is pushing to end all that talk about megapixels, instead coining the term "ultrapixels" to describe the technology behind its camera in the One smartphone.

The poor old megapixel has been stuck between a rock and a hard place over the past few years. Camera and smartphone companies have struggled to find the sweet spot between effective resolution, quality images and marketing speak. After all, many consumers still value a bigger number over actual real-world performance.

We may have thought that the megapixel race was all but won in 2009, when camera manufacturer Olympus threw its hat in the ring, saying that the megapixel wars were over. Just a few years later, though, it was on again in earnest, with 16-, 24- and even 36-megapixel sensors emerging in the camera world, and Nokia's 41-megapixel PureView throwing down the gauntlet in the smartphone realm.

Most smartphone and camera manufacturers push a bigger number with each successive generation of product, so it's reassuring to see HTC taking a step back from marketing a number just for the sake of it.

The stand-alone camera market continues to falter as more people pick up a smartphone rather than a point-and-shoot. The HTC One takes technology from both worlds to lure photographers across to mobile photography.

Camera specs

While the term "ultrapixel" is a clever marketing term that makes it sound like there is a lot of new technology at play, the top-line imaging specs aren't all that different from technology we've seen before in compact cameras:

• 4-megapixel 1/3-inch backlit-CMOS sensor

• f/2.0 lens with optical image stabilisation (two-axis)

• 28mm wide angle (35mm equivalent)

• 1080p video at 30fps, 720p at 60fps, 1080p HDR (high dynamic range) video at 28fps, 768x432 at 96fps

• H.264 encoding at 20Mbps

• Still image output resolution at 2688x1520 pixels (16:9)

Yes, that's a 4-megapixel sensor — not 14. We know by now that a camera's megapixel rating is not the be-all and end-all of image quality, but there are some reasons why resolution is important.

For starters, a lower output resolution means that you have less scope for cropping into photos. Four megapixels may be more than adequate for web-sized snaps, but anyone who wants to make enlargements or precise adjustments will have less to work with.

To be fair, the overwhelming majority of smartphone users will not readily be thinking about cropping, printing or making enlargements from their photos — especially seeing as many apps only support lower-resolution photos for editing purposes. This is really only something that will concern keen photographers who want to do more with their smartphone images.

The sensor in itself is not particularly large when compared to point-and-shoots. Most stand-alone cameras have sensors that typically run in the region of 1/2.3-inch or more. What does set the sensor apart is that the photosites themselves (at 2.0 micrometres) are larger than those found on competing phones, like the Nokia Lumia 920 and the iPhone, and more or less the same as cameras like the Canon G12.

All this talk about specs doesn't really mean much on paper. After all, the proof is in the pudding — or, in this case, the photos. Unfortunately, taking a look through the sample images provided on HTC's site fails to demonstrate what sort of photos this camera can actually create.

The six images on the camera page are filled with smiling faces, sharp subjects and ample light. They are, however, at such a reduced resolution that it becomes nigh on impossible to glean any insights into real-world performance. The comparison shot showing the One's camera stacked against a "competitor's" camera is similarly tiny.

Just because the lens has a maximum aperture of f/2.0 — a whole stop faster than the lens that graces many stand-alone cameras at f/2.8 — doesn't necessarily mean that the camera will perform well in low light. It may very well be able to gather more light, but if the image processor and sensor can't adequately resolve it, images may not be as impressive as first thought.

Backlit-CMOS sensors are often cited for their excellent low-light performance, but noise and over-processing can often be an issue.

The One looks like a promising camera phone, though in an age where even the casual photographer is a pixel peeper, we really need to see actual photos from the camera before deciding whether "ultrapixels" are ultra-good or ultra-hype.