HTC One M8 Camera Explained: Is it just a gimmick?
All eyes are on the Samsung Galaxy S5 in the phone world at the moment, but we're also on the eve of discovering what the HTC One M8 is all about. And some of its tech sounds a lot more interesting than what Samsung has to offer.
Right at the top of the list is the HTC One 2 camera. It uses two rear sensors, but not for the sort of 3D photo fun that proved such a flop in the HTC Evo 3D back in 2011. Instead, it wants its photos to look much more like those of a high-end camera. However, as much as we love HTC's desire to innovate, we fear the company may have a gimmick of another flavour on its hands, rather than a mobile phone camera breakthrough.
What is the HTC One 2 camera all about?
HTC is yet to officially announce the second flagship HTC One phone, but our friends over at Pocket-lint have already been told by a source about how the phone's camera will function.
Rather than using a single sensor and lens like almost every other phone on the planet, it has two separate sensors on the back.
At first we thought that the two sensors would take on photo duties in different lighting conditions. You'd use the UltraPixel camera for low-light shots, and a normal one for bright, sunny days. It makes sense as an idea, as the one big problem with the single 4-megapixel UltraPixel camera made to date (seen in the One Max and One Mini as well as the original) is that it simply doesn't offer enough detail.
Just check out our Galaxy S4 vs HTC One photo comparion to see what we mean.
However, what the second sensor is actually used for is quite different. It isn't used to reap 'normal' image data but depth data – hence why it can afford to be a good deal lower-res, or lower quality, than the already pretty low-res UltraPixel sensor. It doesn't make the picture, but rather tells the camera's brain more about the photo taken with the primary sensor.
How it is likely to work in rudimentary terms seems obvious. The 'depth' sensor is offset from the main sensor by an inch or two, and the disparity in the positioning of objects can tell the HTC One 2's camera processor how far away an object is. For example, if you held a finger 10cm away from the phone's camera, it would appear quite different to the two sensors. However, the positioning of a hilltop church 2km away would be almost identical through their eyes. It's the basic principal of parallax in action, and is how 3D cameras discern depth.
What can the HTC One 2 camera do?
By giving the HTC One 2's camera processor depth data, it can effectively single out objects in a scene, applying filters or processes to the foreground but not the background, and vice versa. It's rather ingenious, and the prime use for this is to create a 'shallow depth of field' effect.
Traditionally this is used make photos of relatively close-up objects look more dramatic and vital. By blurring the background, the foreground appears all the more sharp – it's used extensively by portrait photographers, and to great effect.
We expect HTC will use photographer buzzwords such as 'bokeh' in its presentation of the HTC One 2's camera, but the effect is fundamentally fake. It's an automatic 'photoshopping' of your shots. It's not the real deal.
To get to the reason of why we should care, we need to look a little into how real shallow depth of field effects are created. And it's primarily about the lens.
Lenses that create great bokeh are generally those with wide open apertures – the hole where the light gets in. Every camera lens (even mobile phone ones) has an f-stop rating that relates to how wide its maximum aperture is, and the lower the number, the wider the aperture can go. And – generally speaking – open apertures produce more pronounced shallow depth of field effects.
Mobile phones have fixed apertures – the HTC One's is f/2.0, for example – but 'proper' cameras tend to have moving blade systems that open up and close the aperture as needed. However, in pure number terms top-end phone cameras lenses are pretty good. An f/2.0 dedicated SLR camera lens with a focal length of 50mm would able to create superb bokeh (in theory), so why can't an f/2.0 phone?
Creating out of focus backgrounds is a process or diffraction. The light that forms these blurry background bits is bounced around by the various lens elements so that it appears totally different to the way our own eyes would perceive it.
It's not just a blur, it's a form of distortion. Tiny phone camera lenses married to tiny phone camera senses just can't perform the same optical feats. And nowehere is this clearer than in the best examples of bokeh-ified light sources. The HTC One 2 couldn't hope to do anything like this.
What the HTC One 2 does offer is a sort of Instagram-generation equivalent. It's 40 per cent of the effect for two per cent of the effort. And given the sound physics that the UltraPixel idea is based on, we're disappointed to see HTC invest so much in such a photographic 'cheat'.
It is something that makes us all the more appreciative of the Nokia Lumia 1020. That phone has a genuinely pretty large sensor, and is capable of some real depth of field fun. Sadly, pretty uninspiring sales of the phone haven't exactly seen Nokia reap all that many rewards for its efforts.
Are we being snobs?
However, we are – on a level – being snobs here. If it is remotely as effective as the 'forty per cent' we pulled out of a hat earlier, it offers positively loads of creative potential. And that is something to be valued.
If it does manage to awaken a few would-be photographers, the HTC One 2 also has the potential to work as a great gateway phone, one that could give thousands the photography bug. We just hope that HTC doesn't sell the phone as another step to eradicating the need for dedicated cameras full-stop. Because while its effects may look like those produced by £1,000 cameras, they're really the McDonalds Happy Meal equivalents.
Next, read our HTC One review