Yesterday I brought you some full resolution pictures from the Nokia 808’s 41 Megapixel camera, and those represented something of an extreme case. When Nokia made the 808, they didn’t intend on people taking 38 MP photos. In fact the default automatic mode shoots at 5 Megapixels (3072 x 1728) and the image weighs in at about 1 MB, a stark contract from the full resolution (7728 x 4354) photo that can go upto 16 MB or more.
The benefit of shooting in this mode is the oversampling that helps reduce noise and increase color accuracy and sharpness. A 5MP photo from the 41 MP sensor means that each pixel in the 5MP image is the result of the aggregation of about 8 pixels. The result is similar to what you experience when you resize a large photo into a tiny one and it suddenly becomes nice and crisp.
The second advantage of such a large sensor is the ability to zoom. Nokia calls it lossless zoom as unlike traditional digital zoom, there is no interpolation of pixels to get a zoom effect. Because the sensor is so large, the device is still capturing the same 3072 x 1728 image, just without oversampling. This still keeps the image fairly sharp, but now each pixel is not an aggregate of 8 pixels, but lesser depending on the amount of zoom in play. At maximum zoom, the ratio will be 1:1, at zero zoom its 8:1. So obviously, a fully zoomed in 5 MP photo will not be as nice as a 5MP photo without any zoom, because each pixel isn’t benefitting from any oversampling.
To give you an idea of how all this theory works in the real world, I took more than a few image samples with the phone in the automatic ‘PureView’ mode. As always, click on each image to access the full resolution shot.
A zero zoom shot, followed by zooming in with the automatic ‘PureView’ mode.
I was able to get close without turning the image into the interpolated bloat that using digital zoom would have resulted in.
Next, standing across the street this is the picture I would get with a normal cameraphone.
But if I zoom in a little, I can get much closer to the subject.
Again, from across the street.
But if I choose, I could also frame the following.
Or choose an altogether different subject. Zoom does give you a lot of flexibility.
Indoors, with a fair decent amount of light.
With PureView zoom:
I am not sure, but I think I already was zoomed in a little here.
However, PureView lets you get much closer. This is great for macro shots, as you can use PureView to get up close with the subject, even if you are having difficulties focussing because you have positioned the phone too close.
Click though to open the above photo in its full size, then look at the top left corner. Even fully zoomed in, the amount of detail is impressive.
If you are watching these pictures on your monitor or even printing at the 6×4″ or even 8×10″ size, you should get along just fine. Displaying the fully zoomed shots at less than their original resolution will give the images the same pseudo oversampling effect that resizing a normal picture brings. Unless you are looking at them in the original resolution you’d be hard pressed to say any sort of zoom was involved.
PureView is clearly a technology of the future, after using the 808 for a couple of day I have a hard time switching back to the iPhone 4S or even the N8, both of which rely on digital zoom and its useless interpolation to trick users into believing the phones have ‘zoom’. While using a 808, on most days I’ll be happy to zoom in at less than a 100% to allow for some oversampling but if push comes to shove, its good to know that the 808 can handle itself.
Nothing on the market comes close to what Nokia is doing with the 808 PureView. They are once again reinventing mobile photography, just like they did with the N90.
Note: The pictures are from a prototype device, with the final camera firmware still being around 2 months away. The quality can only get better from here.