First up, thanks for the replies... when I started looking for a new camera I was considering D-SLR's and Bridge models like the FZ8 or S5 IS, and I didn't continue looking as I thought I wouldn't be able to master them in time. But now looking at them I think I want the compact size for carrying around.
Originally Posted by Fabula
3mp is sufficient for normal use, with other things being good. But the lowest I've seen available new now is about 6 mp, so that should be the minimum to go for.
More pixels in the same space equals more noise, and no compact camera will be reasonable to use much over iso400. But newer sensors are better at coping with noise, so an older generation 6mp camera may be comparable in noise to a brand new 10mp camera, assuming both are/were decent.
Ideally I would say "go for a full frame camera like a canon 5d, as the noise levels are fantastic", but they cost a packet, and are not what the op was looking for.
The op wanted "to get them printed big enough to go on the wall in the lounge", so definately the more pixels the better. There will be some noise issues at higher sensitivities, but that is inevitable with a compact.
The camera manufacturers are pushing the megapixels as for many people it seems to be the determining factor in buying a camera. Yes, putting a 10mp sensor in a compact camera is overkill. But the newest cameras will have the best features and technology, so unless you decide to go for a Leica M8 or similar, you will sacrifice some slight noise for the better overall package.
Right, think i've got this now... I can appreciate that the smaller the camera the smaller the sensor, so cramming 10mp in a smaller space is going to lead to more noise, and trying to take photos at ISO400up at 10mp on a compact is going to have a lot of noise.
So the question is, what would be the effect of setting a 10mp camera to take photos at 6mp, do you get the noise level of having a 6mp sensor the same size, or is it just using a section of the 10mp sensor so noise will be just as high as taking at 10mp ?