HTC One UltraPixel camera review

The new HTC One, has a lot going for it - a fantastic design, an ultra crisp 1080p display and crazy fast specs. But when HTC announced their new flagship in London two weeks ago, they also surprised the tech world by announcing that the One would feature a 4 megapixel camera sensor. Now, 4 megapixel might not sound a lot, but I have always been an advocate of scaling back megapixel for raw quality for smartphones and digital compacts where it is just physically impossible to cram a large sensor. (Many thanks to the good people at Three UK for loaning the HTC One)

In an age where the megapixel myth is more popular than ever, it took a lot of guts for HTC's designers and management to have actually decided on this, and I admire them for it. From a marketing perspective, this new strategy could easily backfire. But in a post PC smartphone world, where the majority of images are shared and viewed on smartphones via social sharing networks like Instagram, Flickr and Facebook, this renewed emphasis on less resolution in exchange of higher quality images makes total sense.

Disclaimer: This review is based on a HTC One running on a pre-release firmware (version 1.26.401.6). I have been told that the firmware that is due to be released with the retail HTC One will feature a few camera tweaks. I will update this review accordingly when the new firmware is released.

The sensor, which HTC calls the UltraPixel, is a backside illuminated (BSI) sensor measuring 1/3" in size - the same size as most typical sensors found in slim smartphones. But that is where its similarities ends. Because the sensor only packs 4 megapixels of data, HTC was able to increase the pixel size to 4 µm2, roughly less than half found on a SLR's sensor but almost double the normal pixel size found on other smartphones and some leading digital compacts like the Canon S110 and Fujifilm X10. This is a fair upgrade, as HTC's own previous One X has a camera sensor with a pixel size of 2 µm2. The same goes for the Lumia 920. HTC's strategy in having a physically larger pixel is in contrast to Nokia's preference to using multiple sensor pixels to create a single final pixel, in their PureView product.

From a physical point of view, it was the only way to get a reasonable quality imaging module into a slim phone, such is HTC's obsession with thinness. Unflattering reports of Sony Xperia Z's low light performance may also have vindicated HTC somewhat. Whether or not the public would buy into this remains to be seen, and it will take massive amount of effort and marketing to educate a public who has already been conditioned to believe in big numbers.

HTC has also fitted a standard five elements 4mm (28mm in 35mm equivalent) f/2.0 lens with optical image stablisation (OIS) to boot. Combined with the new sensor, on paper the HTC One should be capable of delivering some neat low-light photography. A single but powerful LED flash sits on the side.

If there is one thing the you can count on the HTC One, is its gorgeous 1080p display is so darn beautiful, that, like a Vogue Photoshop editor, it would mask every imperfection and flaw the camera has. After all, with 468 pixels per inch density, camera noise wouldn't be as apparent on a sharp 4.7" display than it would be when viewed on a large display.

With plenty of natural lighting available, the HTC One's camera captures a great amount of detail, but so did the One X's. I have no issue with the One's performance when it came to daytime photography - in fact it exceeded my expectations, proving that even with only 4 megapixel at its disposal, you can still eke every possible detail out of the little sensor. Sadly it appears there is a bug with either the hardware or software, where part of the bottom half of an image would appear blurred. This might be a post-processing issue, and if it is, I hope HTC releases a fix for it soon. If previous firmware updates for the One X and 8X were of any indication, I have no doubt that HTC will issue a fix quickly.

The sensor is a 16:9 variety, meaning to get the full resolution, you will have to leave it at its default 16:9 wide mode. In the past, camera sensors have an aspect ratio of 4:3, so you will have to switch to 4:3 to gain its full potential. I made the mistake initially of thinking that is the case with the HTC One and switched to 4:3 manually, effectively cropping the sensor. Now this is a huge annoyance, as I prefer to shoot in 4:3 or 3:2 aspect ratio as I find 16:9 to be too wide (or narrow) for many shots, particularly portraits. So if you are a 4:3 shooter like me, HTC One is only capable of delivering 3.1 megapixel images, just barely higher than the resolution of the display itself.

When it comes to low light photography, the One excels when put against the iPhone 4S and HTC 8X. Details are sparse, and noise a plenty, but the results are still usable. The OIS is partially effective at reducing blur up to a certain degree, so unless you brace yourself or shoot with a tripod, expect some blurring. On the upside, the One's sensor is capable of shooting up to an ISO rating of 1600. The results aren't horrible, but with a large pixel size, I expected better. In fact I expected it to blow the Lumia 920 away. Still, with HDR mode on, and with very steady hands or a portable tripod, the One is possible of taking some lovely night photography. You will just need to invest in some additional accessories first. Unfortunately, there is no full manual mode, nor any form of aperture or shutter priority modes.

The camera app offers quick access to image capture as well as video capture (up to 720p60 or 1080p30 with continuous autofocus). You do not have to manually switch between the two before capturing - simply press the right shutter button and it will start capturing in whichever mode it was selected for. Filter effects such as distortion, vignetting and fake tilt shift is also applied in real time, shown on the viewfinder at all times so you can carefully plan your pictures around those effects.

Speaking of video, the HTC One can capture videos in 1080p in three modes: slow motion, 720p60 and standard 1080p30 HDR.  The slow motion mode baffles me as it doesn't actually capture in high speed and then play back in slow mode, it actually simply capture a couple of frames per second, and then play back in normal mode. HDR mode doesn't look too different to normal mode. Whichever of the two usable mode you use, the One, like the One X, would sometimes defocus before refocusing. This is evident in the sample videos below. In each cases, the process happens quickly, but it is still annoying to see it. Sadly, OIS does not appear to have much of an impact in countering camera shakes.

Three icons resides on the left side: the flash toggle, HTC Zoe mode (I will come to this later) and settings. The settings allows you access to options, through a very long list, for image cropping, HDR and panorama mode, ISO, white balance, face detection, geo tagging, continuous shooting and other assortment. If you think having to scroll down a huge list of options does not sound particularly intuitive, you are right. This is made worse as there are sub-menus to navigate through as well.

Deep inside the Gallery is an editing mode called Sequence. This mode allows you to edit a Zoe to create a multi-exposure shot. Any camera shooter will tell you how cumbersome it is to create mult-exposure action shots, so the fact that HTC has somehow engineered an easy way to do so, is to be applauded. Here, you will also find the object removal mode. Ever found it annoying when capturing a picture and a stray object enters the background and ruins your photo? Well with the object removal option, you can 'erase' objects easily.

Panorama mode is just as you imagined it. Sweep either left or right steadily, and the One will do the capturing automatically, taking a series of pictures as you pan the camera. HTC's proprietary ImageSense chip works its magic here, processing and stitched captured images in real time. Results are surprisingly good, with the only setback being when the camera pans from an area with different lighting condition, exposing the limitation of the sensor's dynamic range limitations.

The One also struggles to focus at time, though this isn't nearly as bad as the Lumia 920 was on its initial release. This is especially true when it comes to macro photography, with the camera insisting at times to focus on the background, despite prodding the screen to manually focus. Unsurprisingly, the One suffers from narrow dynamic range, but this was expected from the get go. Even expensive DSLR suffers from it, so it wouldn't be a surprise that a tiny 1/3" sensor would suffer from poor dynamic range. The HDR mode is also a bit of a hit and miss, creating images that a tad more overexposed than it should. Having said that, images are still a bit more natural than the old HDR mode as seen on the One X.

But if there is one thing the One almost get things perfect, it is the auto mode. Every image I have included here are set on 'Auto' mode, and the colour accuracy is as accurate as you can get to real life (at least when viewed from my laptop's display - after all not all displays are created equally). With the exception of poor dynamic range and hit and miss HDR mode, the white balance is spot on. The only thing HTC needs to fix now is the metering.

With the HTC One, HTC also introduced a new social sharing network called Zoe Share. The aforementioned Zoe Mode is available right on the camera's viewfinder and, when engaged, will capture up to 20 continuous 4MP images and a 3 second video. These images and video is then mixed together, and uploaded to online to Zoe Share. It's effectively a new way of capturing memories, by splicing together a mixture of stills and video to create a short video preview to your life, like a less sophisticated Vine.

These images can also be used to create sequences, basically a multi-exposure image.  Any camera shooter will tell you how cumbersome it is to create mult-exposure action shots, so the fact that HTC has somehow engineered an easy way to do so, is to be applauded. Zoe is rather a neat idea, and the execution is smooth but I can't imagine it taking off. The fact that 'Zoe'es is proprietary confines it immediately within the ultra niche. This is made worse by the fact that HTC One is the only product that supports it.

And as impressive as the low light performance of the new HTC One is, I found that its day light performance to be equal to that of other modern slim smartphones like the HTC 8X and Galaxy S III, though it falls short of the N8 and PureView 808. In fact, for those who prefer to shoot in daylight, the 4MP resolution might prove to be a limitation, particularly if you have to crop. So whether or not HTC made the right choice to go with a 4MP sensor will depend on whether you believe a trade off in resolution for a decent low light camera is worth it, and the kind of pictures you will be shooting. If you are into low light mobile photography, the sensor here picks up more light than the iPhone 4S.

As a smartphone, the HTC One is brilliant. As a camera, it takes a step forward, and another back. Thanks to the hype that HTC themselves help create, one would expect a smartphone camera that is as revolutionary as the Nokia 808 PureView was, just one designed for super slim smartphones instead of fat cameras with phone functionality attached. Is it worthy of the hype? No. Will it replace your dedicated camera? No. But that isn't the point of the One. As a phone that you will always carry with you, the One is capable of 90% of your photography needs.

Despite my initial reservations, more than 1200 pictures later, I believe HTC made the right choice here. Even if the execution isn't perfect, HTC has gotten people into talking about the megapixel myth again, and how it is okay not to chase big numbers.

And that is a good thing.

If you have any questions regarding the HTC One, feel free to ask via the comments below, or on twitter.

Resized but otherwise unmolested samples:

Full res samples are available via my Dropbox.

Note: This review is based on a HTC One running on a pre-release firmware (version 1.26.401.6). 

Update: More samples here.