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p.1 #14 · Nikon Really Cutting Canon's Lunch- G9 Clone but Better? | |
Jman13 wrote:
Well, that's true if the sensor is actually using all the pixels, even with noise. The thing is, due to noise from the tiny sensor, the 12MP image on my G9 has a bit less detail than the 8MP image on my 30D. I'd like to see a balance between resolution and noise, such that at low ISOs, the sensor is actually resolving all the detail it can. Yes, I've reduced my G9 files at ISO 800 to 6 MP files, and they look quite good. I'm pleased with the camera overall, but so many of those pixels are wasted to noise because of the insane pixel density that they'd be better off halving the resolution in my opinion.
I think you're still not thinking clearly about this. Pixels are not wasted to noise. Even when the signal to noise ratio is so high that noise dwarfs the signal of an individual pixel, statistically, the signal is still there, on the macroscopic scale. That's why looking at 100% onscreen magnification is so misleading. You could have a 200 megapixel file with disgusting noise, and find that it makes a better print than a 12 megapixel file with barely perceptible noise. Whether your sensor 'is actually resolving all the detail it can' is of purely academic interest when considering the dirty compromise of capturing usable image data at high ISOs.
Here's a quote from a very interesting page about these issues:
"The above DSLR/digicam comparison outlines the extremes of what may be possible with current or near-term technology, if digicam pixel densities were scaled up to full-frame sensors. The fact that a digicam's performance is in the same ballpark as the best DSLR's when referred to fixed spatial scale, suggests that the problems with noise in digicams are not due to their ever smaller pixels, but rather it is due to their small sensors."
The article is here:
http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/noise-p3.html#bitdepth
One interesting point in the linked page is that the appropriate metric of signal to noise ratio per square meter of sensor is about the same on the 1D3 and 1Ds3. Since the s has a larger sensor, it is less noisy per image.
Edited on Jul 08, 2008 at 05:04 PM
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