I have also heard, from pocket calculator collectors, that you get real
good pictures if you photograph them outside on a bright but overcast day.
I haven't tried this myself yet, but I suspect that because all non
specialist films are designed for outside use and that you don't get
shadowing or light source reflections you end up with good clear pictures.
Obviously taking a box of calculators outside is a lot easier than some of
the larger computers, but I am going to try it in the near future as we
now have a larger garden with areas that are not in shadow from
overhanging trees.
One person said that his preferred background was the concrete floor of
the top layer of a multi-storey car park!
--
Kevan
Collector of old computers:
http://www.heydon.org/kevan/collection/