Just a little info I know about digital cameras.
 
I have had no experience with the low end cameras and can not say much about
the quality of the imiages.
 
However, on our summer field school our unit was just in front of the photo
school for the military at the Naval Air Station Pensacola.  As with
everything the military has a leg up and have very hi-tech 35mm digital
cameras.  These cameras are able to store up to 60 images at a time (I think)
and the quality is excelent.
 
The down side is they currently cost in excess of $10,000 not to mention the
computer equpment necessary to handle the images.  In talking with an
instructor at the photo school he said one important thing about digital
cameras, and that is the quality of the images is directly related to the
quality of the printer being used, which again runs into the thousands of
dollars.
 
From visiting with the instructor it would seem that at this time the costs
involved for digital camera use in archaeology is not a reality for the vast
majority of the archaeology world, but it is something to watch for in the
future.
 
R. Moon
Uni. of West Florida