High res pics/scans of coins?

What cameras do you all use to get nice, clear pictures of coins? I
was only able to get some fairly decent ones with my 4.0MP camera, and
terrible with my 5.0 (cheaper) one. With my scanner, at 4800 DPI, it
was still a little blurry (though it was still in a plastic flip-case
that I didn't want to take it out).

Here is a scan of the date of my 1942/1, just to give you an idea of
what I'm talking about:

http://img394.imageshack.us/my.php?image=194219kv.jpg

I've seen people give great, clear scans. The date on the coin is nice
and crisp (much nicer than the scan if you look through a magnifying
glass), and the color is a bit off on the scan.

Both my cameras are Sonys, and my scanner is an HP all-in-one 3200.

i'm going to guess that your scanner uses LEDs rather than a lamp. LEDs
are cheaper than light bulbs so are popular on cheap scanners but they
have one big flaw: poor depth of field. that is, the area that remains
in focus is literally a paper-thin section closest to the glass and the
farther off you lift an object to scan the more out of focus.

ras

ras wrote:
i'm going to guess that your scanner uses LEDs rather than a lamp. LEDs
are cheaper than light bulbs so are popular on cheap scanners but they
have one big flaw: poor depth of field. that is, the area that remains
in focus is literally a paper-thin section closest to the glass and the
farther off you lift an object to scan the more out of focus.

ras

Hmm, maybe I will take it out of its plastic just this once and find
out.

On 30 Nov 2005 21:05:18 -0800, "ras" wrote:

i'm going to guess that your scanner uses LEDs rather than a lamp. LEDs
are cheaper than light bulbs so are popular on cheap scanners but they
have one big flaw: poor depth of field. that is, the area that remains
in focus is literally a paper-thin section closest to the glass and the
farther off you lift an object to scan the more out of focus.

ras

Actually it is the type of image sensor that controls the depth of
field. From a post by Ray Niblett in a "Camera vs. Scanner" thread
from October of 1999:

"Depth of field in a scanner is greatly affected by the technology
used in the scanner. CIS (Contact Image Sensor) scanners have very
limited depth of field. This technology is found in many of the newer
inexpensive scanners. The older CCD (Charge Coupled Device)
technology has much greater depth of field. UMAX web page lists a +/-
3mm depth of field for CCD and +/- .3 for CIS.

CIS is cheaper and smaller so the scanner itself can be made smaller.
Probably the two main reasons they are commonly used.

A CCD scanner is going to be better for scanning coins. Still, I
think a slabbed coin is going to be several milimeters off the glass
plate pushing the CCD scanners to their limits."