Originally posted by rjcassara PureView means they use all 41 megapixels to take the image, but they take clusters of 7 pixels, and average them to obtain a single pixel. Cropping just throws away the extra pixels, Nokia is using the extra pixels to reduce noise, so it's not just a marketing word.
Yes, well, they're cropping and then averaging a cluster of pixels -- which is exactly the same thing as downsampling, whether it is done in firmware or in Photoshop isn't really relevant. Granted, if they're doing the averaging in the analog domain before the ADC conversion takes place then it is likely to produce slightly better results, but it's still basically the same thing. It IS marketing-speak when they dream up special ™ ® words for this process. It makes a lot of sense to do it this way in a camera phone, but there's nothing new or unique about it. The news is they're using a sensor with an insane amount of pixels per square millimeter, so the process is likely to be far more effective than previous attempts to do pixel-binning and/or cropping in-camera.
It is ALSO a marketing lie when they claim that the pixel binning process somehow turns individial pixels in the resampled output picture into "true RGB pixels". Nope, sorry. A downsampled cluster of Bayer-filtered pixels is just that, a downsampled cluster of Bayer-filtered pixels. Sure, resolution and colour fidelity is better, but this is not a Foveon sensor or anything like it.
Originally posted by falconeye: I talked about equivalent properties and they DO change. You must consider a camera system, not a part like a lens. And cropping DOES change a camera as a system.
But the fact is that the "equivalent" focal length never ever changes. A picture taken at 35 mm-e is still 35 mm-e no matter how hard you crop it. As you know, focal length does not only determine field of view, but also depth of field and perspective, among other things, so it is completely useless to talk about the focal length changing in this case, because it does not. It's 8 mm (35 mm-e) no matter how you slice it.
It's not zoom in any sense that the word has ever been used thus far in photography; it's exactly like the common practice of taking a bird picture with a 300 mm lens and cropping it to a 600 mm-e field of view (because you have pixels to spare on your shiny new K-5.) Yeah, it now looks like the bird is closer, but it's still a picture taken with a 300 mm lens, and now you have less resolution per inch when printing. Cropping can not ever change the focal length, which is a physical property of the lens.