I asked which camera I should buy The Sony DSC H1, the Canon S2IS, the Panasonic FZ20/FZ30 (or FZ7), but do not think I asked the right question to get what I am seeking help for.

Is a 5 Megapixel enough Megapixels to get quality large prints to hang on walls or would I need to get a camera with 8 or 10 megapixels? Or is megapixels what I even need to be looking at?????

I think you can use this as rule of thumb for good quality prints (looks good when looked from close):
Divide image's pixel size, for example 3264 x 2448 (~8MP) by 250 for getting size in inches or by 100 for getting size in centimeters.
For wall poster (which you don't look from ~20cm/8" distance) you could propably double dimensions.

(2592 x 1944 for ~5MP)


Also if you have time (+tripod) for shooting you can zoom in+take multiple shots and compile very high resolution panorama from those separate shots...
Clearly this works only for stationary target shots.

http://www.ptgui.com/
http://www.tawbaware.com/maxlyons/index.html

Well, I have a Panasonic FZ4 for birdwatching, but my preference is for a tiny camera which I can have with me always. For that I have a Konica/Minolta X 50 (5 MP), and my wife has an Xi (3 MP).

We have 12"x18" prints from both of these cameras, and they are BETTER than similar blow-ups from 35mm slides (which tend to show annoying grain in the sky).

The only caveat is that you must "resample" to be sure of smooth edges on things in the picture printed: use a program like PhotoShop Elements Image>Resize & select the bottom line in the window that results, changing the pixil count from the 72 it will probably show, to 300.

These prints are JUST FINE for the wall, and even at normal reading distance, maybe if you want to look at them with a magnifying glass, they won't be sharp enough, but in the real world, just fine.

Most people will never do larger than 8x10, which anything 4+ megapixels will do an outstanding job for. I have heard storys of poeple cropping 3 mp imagesand getting good 8x10's.

I have a large format printer and like 13 X 19 prints for my wall. If I don’t have to crop at all the best 13 X 19 I can get from a 7Mp image is around 162 PPI. Some people feel that 300 PPI is optimum but I agree with E.T. that 250 PPI is about as much as you can see even under magnification. I find that 180 PPI is around the point of diminishing returns where you have to look hard to see any improvement without getting real close. But 250 PPI is well over twice the pixel density of 162 PPI and I do see improvements over 162.

I have printed 13 X 19 prints from 5Mp images. The most I can get is 135 PPI, and that isn’t really great. The subject matter is significant to how many pixels you need. Some things don’t look too bad at 135 PPI and others could obviously use more definition. People tend to look closely at photos of people unless it is a full face portrait. You wouldn’t want to hang a 13 X 19 group shot from a 5Mp camera.

Unless I have a lot of time to frame a shot I usually end up cropping a tad. That doesn’t help either.

An upsample will smooth out an image with too few pixels, but it doesn’t help the resolution at all. I have the Genuine Fractals plug-in for Photoshop and actions set up for stepped interpolation – both of which do a better job than bicubic or bicubic smoother. I’ve also tried the QImage upsample and find that maybe a little better than bicubic but not quite as good as GF or SI. None of them are magic. If you start out without enough resolution you end up with a smoother print without enough resolution.

If you want large prints for your wall get as many Mp as you can.

slipe, I'm curious what your expieriances have been with different cameras at similar print PPI. The difference from my 5mp A1 to the 6mp 5D has very little effect on print resolution but the image quality is noticably different. Exposure seems to have a noticable effect too but maybe thats just from noise and post processing. I have certainly seen how subject affects the apearance of the print at lower resolutions! I made a few 8x10 prints of landscapes from my old 3mp olympus and they were fantastic, but a couple of the 8x10's from my A1 left me wanting more (to be fair, I had used higher iso settings and there were artifacts from the noise removal process).

Thank you for all your input. I definetly want to hang large prints on walls so I'll have to go with an 8 MP or higher. But for now price wise I'll have to buy 8 MP.

If you have any input on 8MP cameras, I'm all ears.....

Thanks again, K.P.

tmoreau I do a LOT of post processing before I print something. 16bit files from raw looked a little better than my other 5Mp camera, but not by a lot. Large prints from my little 7Mp Z750 look better than anything I could do with raw and 16 bit in 5Mp. I have no doubt a 6Mp image from a good DSLR would probably look better than 7Mp from the little Casio because of lower noise and more dynamic range. But the 7Mp image would have a little better resolution if you looked closely.

K. Pitre The only camera you listed with 8Mp is the Panasonic FZ30. If you want a long stabilized zoom it is about the only player. The Fuji S9000 is 9Mp and doesn’t have stabilization but it good through ISO400. You would get better shots of still subjects with the FZ30 and have better results with action with the S9000. The only other player right now is the 8Mp Nikon 8800, but the lens is so slow at full zoom you lose a lot of the advantage of stabilization.

Yep, the digital noise is a big, big factor. I try to keep it to the lowest ISO setting, and as I have stated 3 MP will make whatever print FOR THE WALL you might want, and even for regular reding distance.

Panasonic FZ30? The FZ4 & 5 are cheaper & smaller. I have done tripod tests with both and with Minolta Z6 - and the Lumix FZ4 WINS. Same size sensor as the others, and way less digital noise. So I got the FZ4 for birdwatching, but still carry the tiny Minolta X50/ Xi as primary camera:

"The camera you have WITH you, gets the picture." -Erik

I have 2 8.5x11 prints on my bedroom wall, one taken with a Fuji e550, and the other with a Fuji F10, and both show no sign of pixelation whatsoever, dispite the fact they were printed on a canon inkjet. Both are 6MP images. I have an 8x10 image also which was taken with a compact Olympus 35mm, on a tripod even, but it seems much less sharp and chrisp than the digitals. It's resolution almost seems less, and it was printed professionally on Kodak paper. I have yet to have my F10 printed on larger sizes, but plan to shortly. 72PPI is a bare minimum IMHO, and you must have at least 4x the DPI to utalize the pixels properly, which would be 300DPI for 72PPI. This would be good for a poaster viewed from a distance. Double that is required if you are going to look very closely. At 13x17, I would get about 170PPI with 6MP, which should be pleanty. Unless you are going bigger than that, 6MP should be enough.

More important is how much detail the camera really shows. Here is what I am talking about:

http://www.dpreview.com/reviews/pana...z30/page15.asp

the FZ30 does a good job of maintaining the resolution, while other similar MP cameras are not nearly as good.

I would take a look at the Fuji S9000 for max resolution. It has nine MP, and does perform better than the Z30 on the resultion test.

http://www.dpreview.com/reviews/fuji...000/page13.asp