According to the method on the net, I try to take all black photo to test my new SD700, however under the manual mode, ISO set to 100, highest res, superfine, the photo is only about 700KB. My friend with his Fuji F30 can take 2MB one. Am I missing some configuration or is it the way Canon process its photo?

My guess would be that it's all in the compression that's used and the format the file is in.
Using Paint Shop Pro I created a 3200x2400 @180dpi colored it all black and saved it as a jpg file using the Lowest compression available.
The file size was only 213K.
An LZW compressed TIF file came out at 555KB

high MP doesnt mean better quality if thats what you're thinking.


My Casio Exilim EXs500 takes okay pictures..and the picture size is roughly 1-2MP a pic
My Nikon D50 takes outsanding pictures on Jpeg Normal and the picture size is roughly 700-900KB

I'm not sure but the jpg file you created in Paint Shop Pro is the true black, but the photo I took is the camera's recreation of the object, for example, your jpg file may store the info that every pixel is black, however since the pixels of the image I took aren't identical(I just focused at a artificial dark area), the photo is bound to be much larger. What concerns me is that what if the camera is not good enough to identify the subtle difference between these pixels.


I understand your statement. The quality is more about accuracy I think. I just don't understand why my friend can take a 3 times larger all black photo at the same settings (ISO, shutter speed, etc)

BTW, do you by any chance know about the vertical/horizontal resolution in the photo properties? Why put this kind of info there?
Thanks.

Some cameras use a more efficient compression ratio than others; the differences are barely noticeable. Think of it like TIFF vs. PNG or 95% quality JPG vs. 90% JPG.

Maybe his picture is filled with low noise that is hard to distinguish due to all the black.