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whiskers Jan 27, 2006 10:58 AM

i was reading up on ccd sizes and started thinking, since the FZ20 has a 1/2.5 " CCD size, it seems logical that decreasing in-camera image resolution (say, from 2560x1920 to 1024x768) would result in better quality images.

however, somehow i think i'm terribly wrong and the camera simply resizes the images automatically instead of using more CCD bins to record bigger areas of the image.

can someone shed more light on this microns / megapixel ratio for me, i'm feeling a little ignorant.

José A. Jan 27, 2006 1:28 PM

..I was wondering the same a while ago about my FZ10, I was going to run some tests and then I just...

forgot about it.

squirl033 Jan 27, 2006 5:32 PM

if you select a lower resolution, the FZ20 still uses the entire sensor for each photo, and just resizes the image internally. the FZ30 does something just a bit differently when using the so-called EZ-Zoom to increase magnification beyond the lens's actual 12x. at the higher selectable zoom settings, like 15.3x of 19x, it focuses the image on only the center portion of the sensor, and records only that portion of the image data. the restof the time,i believe it uses the entire sensor.

the pixel density on the sensor remains the same, though,regardless of whether you use it all or just part, and pixel density has abig impact on image quality. themore closely packedthe pixels are, the more susceptible they are to heat build-up, which causes noise. the best way to combat that is to put a modest pixel count on a large sensor, which produces a relatively low pixel density. that's one reason the Canon 10D, for example, produces such clean, silky smooth images... it's only a 6.3MP camera, but it uses a 22mmx15mm sensor. for comparison, the FZ30 puts 8MP -30% more pixels - on a 1/1.8" sensor that's 60% smaller... no wonder the FZ is noisier!

the FZ20 is "only" 5MP, but uses an even smaller sensor than the FZ30, and the pixel densities are about the same, which is why most of us were a bit disappointed with Panasonic for falling into the megapixel race, rather than giving us a larger sensor with a modest pixel count. the FZ30, for example would produce much cleaner images if they'd used the same 1/1.8" sensor, but made it a 6MP camera instead of 8.

all that said, the "noise problem" with the FZ's has been pretty well beat to death on this forum, and the consensus is that if you avoid high ISO settings, and have access to a good NR program like Neat Image or Noise Ninja or Picture Cooler, the noise thing really isn't an issue.

whiskers Jan 27, 2006 9:03 PM

ah, that's what i thought. shame that the FZ20 has the same sensor size as my old canon s330. but for that price i'm asking too much, the FZ20 is great enough. thanks for your help.

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