Thanks Romillyh for your response and examples from your website. Apologies for the time taken to respond, but I managed to mess up my login to the forum, but am grateful to Ian in admin for sorting it out for me.

So when you save to a smaller pixel resolution does that also reduce noise when shooting at the same ISO rating? If it did, then I think that would be a strong indication that the CCD is used more efficiently at lower resolutions and therefore less noise is created.

I doubt this is the case though as I have never seen this as a workaround for increased noise levels, so I expect the full quota of megapixels are still captured, irrespective of how many are saved.

This would seem to be born out by the fact that subsequent to posting this question I have read that the maximum optical zoom is rated higher when saving in lower resolutions. Reportedly, this gives you up to 21x for 3-megapixel image recording, 17.1x for 5-megapixel and 13.4x for 8-megapixel recording.

This must mean that even at lower resolution saves, the full 10 quota of 10 megapixels are being captured and the camera is just cropping from the centre of the CCD, i.e. effectively using a smaller CCD but with the same density of data.

Yesterday evening I checked out the documented size of the Panasonic FZ50 CCD. It is reported as 1/1.8" which compared to more expensive DSLRs is considerably smaller, at least as I understand measurements because the specs I found for DSLRs were reported in millimetres in two dimensions. I assume the single measurement is taken diagonally?

Of course, the more you pay for the more you get, but for example with a Canon EOS 300D which is not a great deal more at about £200 or so more, its CCD is reported as being 22.7 x 15.1 mm. By my reckoning that would make it about 1" compared to the Panasonic's 1/1.8" (0.55"?), or over 4 times as big - assuming my maths are correct!

That said, all super-zoom digitals like the FZ50 seem to have similar CCD sizes so comparing like for like is fairer. I see the 9 megapixel Fuji Finepix S9500 is reported to have a 1/1.6" CCD. Has anyone compared the performance of this model with the FZ50?

In conclusion, from my limited understanding it would seem that this pixel stuffing in super-zooms is the major factor in their under performance compared to what they could do if there wasn't such a pre-occupation with high megapixel ratings. The same of course happens with digital camcorders where manufacturers love to blag on about 560x digital zooms as though that was a major reason to buy one against another. For the gullible maybe. Squeezing 10 megapixels on to a FZ50 CCD when compared to 6 megapixels being recorded on an EOS 300D CCD which is 4 times bigger seem nonsensical.

However, in my assessment above I may have got the whole thing wrong, so would be pleased to receive feedback to correct my thoughts/opinions on this.

Peter