> [EMAIL PROTECTED] wrote: ...
> I don't know about D60 (nor D30) but 2820 dpi scans (with fixed
> focus 1000 Euro home film scanner) from Sensia 100 slide film
> (EF50/1.8 at f5.6) clearly beat images from Canon G2 4MP at ISO50
> (at f4) resolution wise. ...

Hi Vesa,

You bring up a very good point. Currently all Canon digital cameras use a
single chip sensor. This include D30, D60, 1D, and all the powershot and DCS
cameras.

The single chip sensor provides information at about half the stated pixel
resolution because of the "Bayer" colour filter, typically RGBG. In a 6MP
sensor, there is one red pixel for every 4 pixels in the stated resolution.
In the worst case, if you look at only the Red channel, that's only 1.5
Megapixels of "real" information, and the rest produced by (very clever)
interpolation. So, "6MP" is really 1.5MP red, 3MP green, and 1.5MP blue.
[To simplify this argument, I am ignoring extra information produced by
overlap in spectral sensitivity].

On the other hand, full bit-depth techniques, like 3-CCD devices, or the
Foveon X3, or your film scanner, generates colour information at every
pixel. 6 Megapixels is 6 megapixels of red, 6 megapixels of blue, and 6
megapixels of green.

This is likely one of the reasons that your desktop scanner produces better
images than your Canon G2.

And that is why I am waiting for a full-frame (24x36mm), full-bit depth
sensor that takes EF lenses.

Quiz time: There already exists a camera that does one, but not the other
:-) Does anyone know which one?

Cheers
Julian Loke

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