We still can't quite believe that we weren't just imagining it and that Nokia really did launch at 41-megapixel cameraphone at Mobile World Congress 2012 this week - the Nokia 808 Pureview.
But the real surprise is that instead of achieving such a ridiculously high pixel count by reducing the size of the individual pixels or resorting to interpolation, Nokia has actually done precisely the opposite.
It's all about microns, you see – a fact I've become well acquainted with thanks to Nokia's wonderfully revealing PureView imaging technology white paper (PDF). A micron is one thousandth of a millimetre, and it's the unit of measurement used to express the actual size of individual pixels.
Pixels, of course, we're familiar with. The pixel count is the first thing we want to know about any camera, and it's what we're playing around with when we crop, edit and resize images digitally.
Now obviously the more pixels you have in a digital image, the more flexibility you have in being able to crop to a small part of a larger image without the image becoming blurred.
But before any of that, each of those pixels has to be captured individually by your camera's image sensor, and image sensors are only so big. In practice, then, if you're looking to increase resolution without affecting the size of the image sensor overall, you have to make each pixel smaller.
That's generally how mobile phones have typically been able to up the megapixel count of their cameras until now: they've been fitted with a newer generation of image processor able to capture light using pixels that are physically smaller.
The problem here is that pixel performance is affected directly by the amount of photons each pixel can collect: and as a rule, the smaller the pixel, the fewer photons it can absorb.
Now like most areas of consumer technology, advancements are being made all the time, but the prioritising of high megapixel counts means manufacturers often adopt new generations of more compactly packed image sensors as soon as they're available, despite early iterations having clearly been shown to deliver compromised performance on an individual pixel level.
It's this same principle that's behind the widely held belief that dedicated cameras will always take better pictures than mobile phones, regardless of the headline resolution.
Yes, there are other factors, such as the quality of the optics, but a “full frame” image sensor offered by a high-end digital SLR is many times bigger than the sensor inside your average mobile phone, meaning each pixel is bigger too.
To see this difference in practical terms, check out our image sensor comparison diagram above and compare the size of the full frame sensor even to the next biggest example, the APS-C sensor. The difference is significant. Now take a look at the smallest sensor, which is the one you'll find inside the Apple iPhone 4S (it's worth pointing out that these will be larger than 1:1 representations on most screens).
Now we're not doing this as any kind of under-handed dig at the iPhone: its 8-megapixel camera is without question one of the very best mobile phone cameras around today.
We've included it firstly to give you a sense of just how big a factor this size difference between smartphones and high-end cameras really is, and secondly, to show just how unusually large the Nokia 808 PureView's sensor is for a mobile device.
The 808 PureView's predecessor, the Nokia N8, was widely regarded as the best cameraphone in the business, and looking at the size of its image sensor compared to the latest iPhone's, you can immediately see one of the main reasons why.
But both of these fine cameraphones pale in comparison to the huge 1/1.2in sensor inside the Nokia 808 PureView.
Getting back to those microns, the pixels on the iPhone 4S and Nokia 808 PureView are actually the same size – 1.4 microns – as opposed to the 1.1 micron pixels on some new mobile phones. For the record, the Nokia N8's sensor has 1.75-micron pixels, though of course it's a couple of years old now, so effective pixel performance is probably about on the same level.
Compare that to the new Nikon D800's 4.8 micron pixels (on a 36.3MP sensor, let's not forget) and pro photographers can clearly rest easy for now.
More interesting, however, is the fact that the newly announced Sony Cyber-shot HX20V also has 1.4 micron pixels on what is a smaller sensor than the new Nokia's. We're not for a second trying to claim that the 808 PureView will take better pictures, but what this does suggest is that if some of the lesser lights of the compact camera business were feeling the pinch before from the ever-expanding smartphone industry, they'll be doubly worried now.
