On 5/31/05 11:14 AM, in article 119ovrfcp6bvvb7@corp.supernews.com, "mcola"
<m.colavito@kellardengineering-nospam.com> wrote:

Hi Mike,
The amount of detail, complexity, and color the camera is capturing in a
particular shot also helps to determine the file size.
Hth,
NB

A non-compressed bitmap (where each pixel is "the same size" - i.e.
ten times the pixel count will give a filesize 10 times larger)
would be exactly the same size.  For the format used in most
digicams, JPEG (.jpg), because it allows for different degrees of
(lossy) compression it will result in different resulting file
sizes.   See http://www.photo.net/learn/jpeg/ 

Try this experiment.
take 3 pix at night trying to capture blackness, now put your hand
over the lens and shoot again.
check the filesizes.
Not all black is real black.
the agony of having 16 million colours!
As complexity rises the filesize rises too.
Now check over your biggest filesizes and look at the histogram
that is available in some viewers.
See how the energy is distributed across the colour bandwidth.

Thanks all for the replies.  As I now understand it, ea. pic has diff.
degrees of complexity (pixel wise) and thus jpeg compression results in
differing final file size.  But all pics taken at a certain resolution will
have the same number of pixels in raw format and thus the same sharpness
qualilty.  Basic, but correct explanation?  Thanks again,  Mike