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-   -   Please explain image device type/size to me?! :?: (

hsuthard Sep 20, 2004 10:45 PM

Steve lists the image device for the Sony P150 7mp camera as 1/1.8 , and for the Minolta Z3 4mp camera as a 1/2.5 imager.

How do these numbers compare? Is the second number the size of the image sensor the pixels are sitting on? I know that the more room the pixels have the better they absorb light.

Both cameras use CCD's, although the Sony has a special name for theirs. Not sure what this means.

Please help me unravel this so I can better compare the cameras I'm considering.

Thanks, Holly.

Mikefellh Sep 23, 2004 11:53 AM

1 Attachment(s)
Usually the larger the imager size, the better. If I have two CCDs the same size and one has 4mp and the other has 8mp, the 8mp will have a higher rate of generating noise due to the amount of photosites generating heat on the same sized chip. Steve usually posts the following picture to illustrate size (I couldn't find an actual link to the picture, this is a copy I saved).

hsuthard Sep 24, 2004 5:32 PM


Thanks for that graphic. That was exactly what I needed to see. That shows me that 4mp on a smaller sensor may be quite close in image quality to 7mp on a larger sensor. When you put into play the rest of the factors, and the sample images I've seen, I feel much more comfortable with the 7mp camera.

It seems the thing to look for is noise, so if that doesn't seem to be an issue, I conclude that more pixels are better, as long as you have space for the pics.

Wish me luck--I'm off to buy the 7mp Sony P150!


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