Hey Paul,

Nice scans! Nice Chips...

To answer your question - what I recommend is that one scans their chips at roughly one-to-one (72 - 100 dpi depending on the monitor where the image is to be displayed). For chips that are to be displayed on the screen, I scan at 100 dpi.
Also for printing I recommend 1/2 of you printers max. dpi. For example my printer is 720 dpi, so I also scan (yes two different scans) at 360 dpi.

There is also a school of thought that anything over your printers max dpi divided by 2.5 is a waste of disk space...
I've checked both of these out, and am sticking with what I did in the past (i.e. 360 dpi)

Some people have asked why do I not just scan at 360 and down sample to 100 dpi. The main reason is that doing so looses some clarity (See image below)

Yet to show some details - it is necessary to scan a chip at either 150 or 180 dpi... i.e. to show either mold details or details in elsewhere on the chip.

I hope this helps!

Dick